Answer:
There is enough evidence to support the claim that students study more than two hours per weeknight on the average.
Step-by-step explanation:
We are given the following in the question:
Population mean, μ = 2 hours = 120 minutes
Sample mean, [tex]\bar{x}[/tex] = 148 minutes = 2.467 hours
Sample size, n = 255
Alpha, α = 0.05
Population standard deviation, σ = 65 minutes
First, we design the null and the alternate hypothesis
[tex]H_{0}: \mu = 120\text{ minutes}\\H_A: \mu > 120\text{ minutes}[/tex]
We use one-tailed z test to perform this hypothesis.
Formula:
[tex]z_{stat} = \displaystyle\frac{\bar{x} - \mu}{\frac{\sigma}{\sqrt{n}} }[/tex]
Putting all the values, we have
[tex]z_{stat} = \displaystyle\frac{148 - 120}{\frac{65}{\sqrt{255}} } = 6.8788[/tex]
Now, we calculate the p-value from the normal standard table.
P-value = 0.00001
Since the p-value is smaller than the significance level, we fail accept the null hypothesis and reject it, We accept the alternate hypothesis.
Conclusion:
Thus, there is enough evidence to support the claim that students study more than two hours per weeknight on the average.
Answer:
There is enough evidence to support the claim that students study more than two hours per weeknight on the average.
Step-by-step explanation:
If we let the domain be all animals, and S(x) = "x is a spider", I(x) = " x is an insect", D(x) = "x is a dragonfly", L(x) = "x has six legs", E(x, y ) = "x eats y", then the premises be
"All insects have six legs," (∀x (I(x)→ L(x)))
"Dragonflies are insects," (∀x (D(x)→I(x)))
"Spiders do not have six legs," (∀x (S(x)→¬L(x)))
"Spiders eat dragonflies." (∀x, y (S(x) ∧ D(y)) → E(x, y)))
The conditional statement "∀x, If x is an insect, then x has six legs" is derived from the statement "All insects have six legs" using _____.
a. existential generalization
b. existential instantiation
c. universal instantiation
d. universal generalization
The statement 'All insects have six legs' is converted to 'If x is an insect, then x has six legs' using the principle of Universal Generalization.
Explanation:The process used here is known as Universal Generalization. This principle allows us to infer that something is true for all objects in a particular domain, provided it has been proved to be true for an arbitrary object in that domain. In this case, the statement 'All insects have six legs' has been converted into a formal logical statement using 'x' as the arbitrary object in the domain of all animals. By stating 'If x is an insect, then x has six legs' and using ∀x (denoting 'for all x'), we are using Universal Generalization to indicate this is true for all members of the domain.
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which of the following would indicate that a dataset is skewed to the right? the interquartile range is larger than the range. the range is larger than the interquartile range. the mean is much larger than the median. the mean is much smaller than the median.
Answer:
Step-by-step explanation:
The first two answers could not possibly be correct.
"Skewed to the right" implies that the mean is larger than the median. This is the correct answer.
The mean is much larger than the median is the statement that would indicate that a data set is skewed to the right. This can be obtained by understanding the characteristics of a data set skewed to the right, that is positively skewed.
What are the characteristics of a positively skewness?Skewness refers to the lack of symmetry.Positive skewness means when distribution is fatter on the left.⇒Characteristics of a positively skewness
Right Tail is longer Mass of the distribution is concentrated on the leftMean>Median>MeanHence the mean is much larger than the median is the statement that would indicate that a data set is skewed to the right. Therefore option 3 is correct.
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4. The length of an injected-molded plastic case that holds tape is normally distributed with a mean length of 90.2 millimeters and a standard deviation of 0.1 millimeters. a. What is the probability that a part is longer than 90.3 millimeters or shorter than 89.7 millimeters
To find the probability that a part is longer than 90.3 millimeters or shorter than 89.7 millimeters, calculate the cumulative probability for each scenario and subtract them from 1. The resulting probability is approximately 0.8413.
Explanation:To find the probability that a part is longer than 90.3 millimeters or shorter than 89.7 millimeters, we need to calculate the cumulative probability for each scenario and then subtract them from 1.
Step 1: Calculate the z-scores for both values using the formula:
z = (x - mean) / standard deviation
For 90.3 millimeters:
z = (90.3 - 90.2) / 0.1 = 1
For 89.7 millimeters:
z = (89.7 - 90.2) / 0.1 = -5
Step 2: Use a standard normal distribution table or a calculator to find the cumulative probability for each z-score.
For a z-score of 1, the cumulative probability is approximately 0.8413.
For a z-score of -5, the cumulative probability is approximately 0.0000003.
Step 3: Subtract the cumulative probability for the shorter length from 1 and add the cumulative probability for the longer length.
Probability = (1 - 0.0000003) + 0.8413 = 0.8413
Therefore, the probability that a part is longer than 90.3 millimeters or shorter than 89.7 millimeters is approximately 0.8413.
Assume that the Poisson distribution applies and that the mean number of hurricanes in a certain area is 6.9 per year. a. Find the probability that, in a year, there will be 4 hurricanes. b. In a 45-year period, how many years are expected to have 4 hurricanes? c. How does the result from part (b) compare to a recent period of 45 years in which 4 years had 4 hurricanes? Does the Poisson distribution work well here? a. The probability is nothing. (Round to three decimal places as needed.)
Answer:
a) 9.52% probability that, in a year, there will be 4 hurricanes.
b) 4.284 years are expected to have 4 hurricanes.
c) The value of 4 is very close to the expected value of 4.284, so the Poisson distribution works well here.
Step-by-step explanation:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
In which
x is the number of sucesses
e = 2.71828 is the Euler number
[tex]\mu[/tex] is the mean in the given time interval.
6.9 per year.
This means that [tex]\mu = 6.9[/tex]
a. Find the probability that, in a year, there will be 4 hurricanes.
This is P(X = 4).
So
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
[tex]P(X = 4) = \frac{e^{-6.9}*(6.9)^{4}}{(4)!}[/tex]
[tex]P(X = 4) = 0.0952[/tex]
9.52% probability that, in a year, there will be 4 hurricanes.
b. In a 45-year period, how many years are expected to have 4 hurricanes?
For each year, the probability is 0.0952.
Multiplying by 45
45*0.0952 = 4.284.
4.284 years are expected to have 4 hurricanes.
c. How does the result from part (b) compare to a recent period of 45 years in which 4 years had 4 hurricanes? Does the Poisson distribution work well here?
The value of 4 is very close to the expected value of 4.284, so the Poisson distribution works well here.
A manufacturer of bicycles builds​ racing, touring, and mountain models. The bicycles are made of both steel and aluminum. The company has available 64,600 units of steel and 24, 000 units of aluminum. The​ racing, touring, and mountain models need 17​, 19​, and 34 units of​ steel, and 9​, 21​, and 12 units of​ aluminum, respectively. Complete parts​ (a) through​ (d) below.
a. Set up the Linear Programming problem is x= # of racing bikes, y=# of touring bikes and z = # of mountain bikes
b. How many of each type of bicycle should be made in order to maximize profit if the company makes $8 per racing bike, $12 per touring bike, and $22 per mountain bike?
c. What is the maximum possible profit?
d. Are there any units of steel or aluminum leftover? How much?
Answer:
b. 1,900 mountain bicycles, 0 racing bicycles and 0 touring bicycles to maximize profit
c. $41,800
d. 1,200 units of aluminium is left over
Step-by-step explanation:
a. Let:
x= Number of racing bikes,
y= Number of touring bikes and
z = Number of mountain bikes
Constraints are;
17x+19y+34z<=64600
9x+21y+12z<=24000
x>=0
y>=0
z>=0
b. Maximize P = 8x+12y+22z
Subject to;
17x+19y+34z<=64600
9x+21y+12z<=24000
with x>=0 ; y>=0 ; z>=0
applying simplex method (see attachment);
z=1900 ; x=0; y=0; P=41,800 ; s₁=0 ; s₂=1200
b. The manufacturer are to make 1,900 mountain bicycles, 0 racing bicycles and 0 touring bicycles to maximize profit
c. Maximum profit is $41,800
d. no steel is leftover while 1,200 units of aluminium is left over.
a. The Linear Programming problem is set up as follows:
Objective function:
Maximize profit: [tex]P = 8x + 12y + 22z \)[/tex]
Constraints:
1. Steel constraint: [tex]\( 17x + 19y + 34z \leq 64,600 \)[/tex]
2. Aluminum constraint: [tex]\( 9x + 21y + 12z \leq 24,000 \)[/tex]
3. Non-negativity constraints: [tex]\( x, y, z \geq 0 \)[/tex]
b. To maximise profit, the company should produce 1000 racing bikes, 2800 touring bikes, and 1400 mountain bikes.
c. The maximum possible profit is $97,600.
d. There are 600 units of steel leftover and no units of aluminium leftover.
Let's set up and solve a linear programming problem for the given scenario.
a. Set up the Linear Programming Problem
Let x be the number of racing bikes, y be the number of touring bikes, and z be the number of mountain bikes.
Objective Function (Profit): Maximise P = 8x + 12y + 22z
Constraints:
Steel: 17x + 19y + 34z ≤ 64,600Aluminum: 9x + 21y + 12z ≤ 24,000Non-negativity: x ≥ 0, y ≥ 0, z ≥ 0b. Solution to Maximise Profit
Using the constraints and the objective function, we use a method such as the Simplex method or graphical method to find the optimal solution. Performing these calculations, we get:
x = 1,000 racing bikes
y = 0 touring bikes
z = 600 mountain bikes
c. Maximum Possible Profit
Substituting the values into the profit function:
P = 8(1,000) + 12(0) + 22(600) = $20,200
d. Leftover Steel and Aluminum
Steel used: 17(1,000) + 19(0) + 34(600) = 37,400 units
Steel leftover: 64,600 - 37,400 = 27,200 units
Aluminum used: 9(1,000) + 21(0) + 12(600) = 16,200 units
Aluminum leftover: 24,000 - 16,200 = 7,800 units
Hence, a. The Linear Programming problem is set up as follows:
Objective function:
Maximize profit: [tex]P = 8x + 12y + 22z \)[/tex]
Constraints:
1. Steel constraint: [tex]\( 17x + 19y + 34z \leq 64,600 \)[/tex]
2. Aluminum constraint: [tex]\( 9x + 21y + 12z \leq 24,000 \)[/tex]
3. Non-negativity constraints: [tex]\( x, y, z \geq 0 \)[/tex]
b. To maximise profit, the company should produce 1000 racing bikes, 2800 touring bikes, and 1400 mountain bikes.
c. The maximum possible profit is $97,600.
d. There are 600 units of steel leftover and no units of aluminium leftover.
Nella drove from Albuquerque, New Mexico, to the Garden of the Gods rock formation in Colorado Springs. It took her six hours to travel 312 miles over the mountain road. She came home on the highway. On the highway she took fve hours to travel 320 miles. How fast did she travel using the mountain route? How much faster (in miles per hour) did she travel using the highway route?
Answer:
Her speed on the mountain route was 52 miles per hour.
She travelled 12 miles per hour faster on the highway route.
Step-by-step explanation:
Speed is given by distance ÷ time taken
On the mountain,
distance = 312 miles
time = 6 hours
speed = 312 ÷ 6 = 52 miles per hour
On the highway,
distance = 320 miles
time = hours
speed = 320 ÷ 5 = 64 miles per hour
This is greater than the mountain route speed by 64 - 52 = 12 miles per hour.
Answer:
Speed at mountain route = 52 miles/hour
Speed at highway route = 64 miles/hour
Difference in speed = 12 miles/hour
Difference in speed = 18.75 % greater than mountain route
Step-by-step explanation:
As we know the speed is given by
Speed = Distance/time
Albuquerque to New Mexico using mountain route:
Speed = 312/6
Speed = 52 miles/hour
Albuquerque to New Mexico using highway route:
Speed = 320/5
Speed = 64 miles/hour
Difference in speed:
difference = 64 - 52 = 12 miles/hours
difference = 12/64*100 = 18.75 %
Therefore, Nella's speed at the highway route was 12 miles/hour greater than her speed at the mountain route.
Nella's speed at the highway route was 18.75 % greater than the speed at mountain route.
The U.S. has a right to eradicate dictatorships wherever it finds them. Dictators crush the right of self governance given by God to all of his children. Dictators suppress liberty and freedom. They sacrifice the lives of their people to satisfy their own corrupt aims and desires. Dictators are vile monsters! They embody the power of Satan wherever they dwell. Down with dictatorships everywhere!
A. No fallacy
B. Suppressed evidence.
C. Argument against the person, abusive.
D. Appeal to the people.
E. Appeal to unqualified authority
Answer:C
Step-by-step explanation:
Argument against the person, abusive as the US government should completely eradicate dictatorship and also curb the incident of abusive things from the dictatorship.
Answer:
This is No Fallacy ( A )
Step-by-step explanation:
This is a no Fallacy statement because it embodies the truth in its argument against dictatorship and its evil deeds/effects on the society that is been ruled by a dictator.
while a fallacy is an argument that is based on invalid reasoning or unjust reasoning while creating an argument in other to win a judgement.in most cases Fallacious argument deceive the audience into believing that the argument is true and passing blind judgement on the subject matter , but with the argument found in the question every part of the argument is a valid reason for the U.S to eradicate dictatorship.
Check that reflection in the x-axis preserves the distance between any two points. When we combine reflections in two lines, the nature of the outcome depends on whether the lines are parallel.
Answer:
No, it depend on reflective surface
Step-by-step explanation:
concave, convex, if plane mirror angle between the two mirrors, the parallel will produced infinity images
Suppose when a baseball player gets a hit, a single is twice as likely as a double which is twice as likely as a triple which is twice as likely as a home run. Also, the player’s batting average, i.e., the probability the player gets a hit, is 0.300. Let B denote the number of bases touched safely during an at-bat. For example, B = 0 when the player makes an out, B = 1 on a single, and so on. What is the PMF of B?
Answer:
The PMF of B is given by
P(B=0) = 0.7
P(B=1) = 0.16
P(B=2) = 0.08
P(B=3) = 0.04
P(B=4) = 0.02
Step-by-step explanation:
Let x denote P(B=1), we know that
P(B=0) = 1-0.3 = 0.7
P(B=1) = x
P(B=2) = x/2
P(B=3) = x/4
P(B=4) = x/8
Also, the probabilities should sum 1, thus
0.7+x+x/2+x/4+x/8 = 1
15x/8 = 0.3
x = 0.16
As a result, the PMF of B is given by
P(B=0) = 0.7
P(B=1) = 0.16
P(B=2) = 0.08
P(B=3) = 0.04
P(B=4) = 0.02
Based on given conditions, the probability of a single (B=1) is 0.160, a double (B=2) is 0.080, a triple (B=3) is 0.040, and a home run (B=4) is 0.020. The probability of player making an out (B=0) is 0.700.
Explanation:Let's denote the probability of a home run as p. Then, the probability of a triple would be 2p, the double would be 4p, and the single would be 8p, all because of the twice-as-likely condition. As these are all the situations in which the player can get a hit, their sum should equal the player's batting average, i.e., 0.300.
So, 8p + 4p + 2p + p = 0.300. Solving this equation, we get that p = 0.020.
Therefore, using the same notations, the PMF of B (probability mass function) would be as follows: P(B=0) = 0.700, P(B=1) = 0.160, P(B=2) = 0.080, P(B=3) = 0.040, and P(B=4) = 0.020.
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A Type I error is:
A. incorrectly specifying the null hypothesis.
B. rejecting the null hypothesis when it is true.
C. incorrectly specifying the alternative hypothesis.
D. accepting the null hypothesis when it is false.
Answer:
Type I error, also known as a “false positive” is the error of rejecting a null hypothesis when it is actually true. Can be interpreted as the error of no reject an alternative hypothesis when the results can be attributed not to the reality.
Type II error, also known as a "false negative" is the error of not rejecting a null hypothesis when the alternative hypothesis is the true. Can be interpreted as the error of failing to accept an alternative hypothesis when we don't have enough statistical power.
Solution to the problem
Based on the defnitions above we can conclude that the best answer for this case is:
B. rejecting the null hypothesis when it is true.
Step-by-step explanation:
Previous concepts
A hypothesis is defined as "a speculation or theory based on insufficient evidence that lends itself to further testing and experimentation. With further testing, a hypothesis can usually be proven true or false".
The null hypothesis is defined as "a hypothesis that says there is no statistical significance between the two variables in the hypothesis. It is the hypothesis that the researcher is trying to disprove".
The alternative hypothesis is "just the inverse, or opposite, of the null hypothesis. It is the hypothesis that researcher is trying to prove".
Type I error, also known as a “false positive” is the error of rejecting a null hypothesis when it is actually true. Can be interpreted as the error of no reject an alternative hypothesis when the results can be attributed not to the reality.
Type II error, also known as a "false negative" is the error of not rejecting a null hypothesis when the alternative hypothesis is the true. Can be interpreted as the error of failing to accept an alternative hypothesis when we don't have enough statistical power.
Solution to the problem
Based on the defnitions above we can conclude that the best answer for this case is:
B. rejecting the null hypothesis when it is true.
Determine whether the two events are disjoint for a single trial. (Hint: Consider "disjoint" to be equivalent to "separate" or "not overlapping".)
Randomly selecting
aa
french hornfrench horn
from the
instrumentinstrument
assembly line and getting one that is free of defects.Randomly selecting
aa
french hornfrench horn
from the
instrumentinstrument
assembly line and getting one with a
dented belldented bell.
Choose the correct answer below.
A.The events are not disjoint. The first event is not the complement of the second.
B.The events are not disjoint. They can occur at the same time.
C.The events are disjoint. The first event is the complement of the second.
D.The events are disjoint. They cannot occur at the same time.
Answer:
D.The events are disjoint. They cannot occur at the same time.
Step-by-step explanation:
Event A = randomly selecting a french horn from the instrument assembly line and getting one that is free of defects
Event B = randomly selecting a french horn from the instrument assembly line and getting one with a dented bell
The two Events are disjoint because they cannot happens at the same time. It is either a french horn is free of defects or it has defects.
Disjoint event is when two event cannot occur at the same time.
A certain mathematics contest has a peculiar way of giving prizes. Five people are named as Grand Prize winners, but their finishing order is not listed. Then from among the other entrants, a 6thplace, 7thplace, 8thplace, 9thplace, and 10thplace winner are each named.If 22 people enter this year, how many complete award announcements are possible?
Answer:
The number of complete award announcements possible are 19,554,575,040.
Step-by-step explanation:
Combination is the number of ways to select k items from n distinct items when the order of selection does not matters.
Whereas permutation is the number of ways to select k item from n items when order of selection matters.
The number of people entering this year is 22.
The number of ways to select 5 people for Grand Prize is, [tex]{22\choose 5}=\frac{22!}{5!(22-5)!} =26334[/tex].
The remaining number of people is, 22 - 5 = 17.
It is provided that the other 5 are selected according to an order.
The number of ways to select other 5 winners is,
[tex]^{17}P_{5}=\frac{17!}{(17-5)!} =742560[/tex]
The total number of ways to select 10 winners of 22 is:
Total number of ways = 26334 × 742560 = 19,554,575,040.
The body temperatures of adults are normally distributed with a mean of 98.6degrees° F and a standard deviation of 0.60degrees° F. If 36 adults are randomly selected, find the probability that their mean body temperature is greater than 98.4degrees° F.
Answer:
97.72% probability that their mean body temperature is greater than 98.4degrees° F.
Step-by-step explanation:
To solve this question, we have to understand the normal probability distribution and the central limit theorem.
Normal probability distribution:
Problems of normally distributed samples can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
Central limit theorem:
The Central Limit Theorem estabilishes that, for a random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sample means with size n of at least 30 can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex]
In this problem, we have that:
[tex]\mu = 98.6, \sigma = 0.6, n = 36, s = \frac{0.6}{\sqrt{36}} = 0.1[/tex]
If 36 adults are randomly selected, find the probability that their mean body temperature is greater than 98.4degrees° F.
This is 1 subtracted by the pvalue of Z when X = 98.4. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{98.4 - 98.6}{0.1}[/tex]
[tex]Z = -2[/tex]
[tex]Z = -2[/tex] has a pvalue of 0.0228
1 - 0.0228 = 0.9772
97.72% probability that their mean body temperature is greater than 98.4degrees° F.
BJ's goal is to have $50,000 saved at the end of Year 5. At the end of Year 2, they can add $7,500 to their savings but they want to deposit the remainder they need to reach their goal today, Year 0, as a lump sum deposit. If they can earn 4.5 percent, how much must they deposit today
Final answer:
BJ must deposit approximately $41,191.39 today to reach their goal of $50,000 at the end of Year 5, considering a 4.5% interest rate.
Explanation:
To find out how much BJ must deposit today to reach their goal of $50,000 at the end of Year 5, we can use the concept of compound interest. The formula to calculate the future value of a lump sum deposit is:
Future Value = Principal Amount x (1 + Interest Rate)^Number of Periods
In this case, BJ wants to find out the principal amount, which is the deposit they need to make today. We have the future value ($50,000), the interest rate (4.5%), and the number of periods (5).
Let's substitute the values into the formula and solve for the principal amount:
$50,000 = Principal Amount x (1 + 0.045)^5
Simplifying the equation:
$50,000 = Principal Amount x 1.21550625
Dividing both sides by 1.21550625:
Principal Amount = $41,191.39
Therefore, BJ must deposit approximately $41,191.39 today to reach their goal.
g Disco Fever is randomly found in one half of one percent of the general population. Testing a swatch of clothing for the presence of polyester is 99% effective in detecting the presence of this disease. The test also yields a false-positive in 4% of the cases where the disease is not present. What is the probability that the test result is positive
Answer:
The probability that the result is positive is P=0.04475=4.475%.
Step-by-step explanation:
We have the events:
D: disease present
ND: disease not present
P: test positive
F: test false
Then, the information we have is:
P(D)=0.005
P(P | D)=0.99
P(P | ND)=0.04
The total amount of positive test are the sum of the positive when the disease is present and the false positives (positive tests when the disease is not present).
[tex]P(P)=P(P | D)*P(D)+P(P | ND)*(1-P(D))\\\\P(P)=0.99*0.005+0.04*0.995\\\\P(P)=0.00495+0.0398=0.04475[/tex]
The probability that the result is positive is P=0.04475.
Final answer:
The overall probability of a diagnostic test delivering a positive result, given its sensitivity and false positive rate, alongside the prevalence of the disease in the population, is calculated to be 4.475%.
Explanation:
The question revolves around calculating the probability that a diagnostic test for a given disease is positive. Given that the disease is present in 0.5% of the population, the test has a 99% sensitivity (true positive rate) and a 4% false positive rate (when the disease is not present, the test incorrectly indicates disease 4% of the time).
Steps to Calculate the Probability of a Positive Test Result
First, calculate the probability of having the disease and getting a positive test result. This is 0.5% × 99% = 0.495%.Next, calculate the probability of not having the disease but getting a positive test result, which is 99.5% × 4% = 3.98%.To find the total probability of a positive test result, add these two probabilities together, resulting in 4.475%.This calculation shows that the overall probability of getting a positive test result, regardless of actually having the disease, is 4.475%.
Many residents of suburban neighborhoods own more than one car but consider one of their cars to be the main family vehicle. The age of these family vehicles can be modeled by a Normal distribution with a mean of 2 years and a standard deviation of 6 months. What percentage of family vehicles is between 1 and 3 years old?
Answer:
95.4% of family vehicles is between 1 and 3 years old.
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 2
Standard Deviation, σ = 6 months = 0.5 year
We are given that the distribution of age of cars is a bell shaped distribution that is a normal distribution.
Formula:
[tex]z_{score} = \displaystyle\frac{x-\mu}{\sigma}[/tex]
P(family vehicles is between 1 and 3 years old)
[tex]P(1 \leq x \leq 3)\\\\ = P(\displaystyle\frac{1 - 2}{0.5} \leq z \leq \displaystyle\frac{3-2}{0.5}) = P(-2 \leq z \leq 2)\\\\= P(z \leq 2) - P(z < -2)\\= 0.977 -0.023 = 0.954= 95.4\%[/tex]
[tex]P(1 \leq x \leq 3) = 95.4%[/tex]
95.4% of family vehicles is between 1 and 3 years old.
Final answer:
Approximately 95.4% of family vehicles are between 1 and 3 years old based on the normal distribution with a mean of 2 years and a standard deviation of 6 months.
Explanation:
To determine the percentage of family vehicles that are between 1 and 3 years old when the age is normally distributed with a mean of 2 years and a standard deviation of 6 months, we can use the properties of the normal distribution.
First, convert the years to a z-score, which is the number of standard deviations away from the mean a data point is. The formula to calculate a z-score is: z = (X - μ) / σ
Where X is the value, μ is the mean, and σ is the standard deviation.
For 1 year: z = (1 - 2) / 0.5 = -2
For 3 years: z = (3 - 2) / 0.5 = 2
By looking up these z-scores on a z-table or using a calculator with a normal distribution function, we find that roughly 95.4% of the data falls between z-scores of -2 and 2. Therefore, approximately 95.4% of family vehicles are between 1 and 3 years old.
Suppose that 275 students are randomly selected from a local college campus to investigate the use of cell phones in classrooms. When asked if they are allowed to use cell phones in at least one of their classes, 40% of students responded yes. Using these results, with 95% confidence, the margin of error is 0.058 . How would the margin of error change if the sample size decreased from 275 to 125 students? Assume that the proportion of students who say yes does not change significantly. As the sample size decreases, the margin of error remains unchanged. Cannot be determined based on the information provided. As the sample size decreases, the margin of error increases. As the sample size decreases, the margin of error decreases.
Answer:
Correct option: As the sample size decreases, the margin of error increases.
Step-by-step explanation:
The (1 - α) % confidence interval for population proportion is:
[tex]CI=\hat p\pm z_{\alpha /2}\sqrt{\frac{\hat p(1-\hat p)}{n} }[/tex]
The margin of error in this confidence interval is:
[tex]\\ MOE=z_{\alpha /2}\sqrt{\frac{\hat p(1-\hat p)}{n} }[/tex]
The sample size n is inversely related to the margin of error.
An inverse relationship implies that when one increases the other decreases and vice versa.
In case of MOE also, when n is increased the MOE decreases and when n is decreased the MOE increases.
Compute the new margin of error for n = 125 as follows:
[tex]\\ MOE=z_{\alpha /2}\sqrt{\frac{\hat p(1-\hat p)}{n} }=1.96\times \sqrt{\frac{0.40(1-0.40)}{125} }=0.086[/tex]
*Use z-table for the critical value.
For n = 125 the MOE is 0.086.
And for n = 275 the MOE was 0.058.
Thus, as the sample size decreases, the margin of error increases.
The red tablecloth has a diagonal of V 10 feet. The blue tablecloth has a diagonal
V 50 Teet. Aaron says that the length of the diagonal of the blue tablecloth is three
times the length of the diagonal of the red tablecloth.
Is he correct? Explain.
the length of the diagonal of the blue tablecloth is five times the length of the diagonal of the red tablecloth. So , Aaron is not correct .
Step-by-step explanation:
Here we have , The red tablecloth has a diagonal of V 10 feet. The blue tablecloth has a diagonal V 50 feet . Aaron says that the length of the diagonal of the blue tablecloth is three times the length of the diagonal of the red tablecloth. Let's find out what Aaron says is correct or not :
Length of red tablecloth = 10 feet = p feet
Length of blue tablecloth = 50 feet
⇒ Length of blue tablecloth = 50 feet
⇒ Length of blue tablecloth = 5(10) feet
⇒ Length of blue tablecloth = 5p feet
That means the length of the diagonal of the blue tablecloth is five times the length of the diagonal of the red tablecloth. So , Aaron is not correct .
Aaron's claim that the length of the diagonal of the blue tablecloth is three times that of the red one is incorrect because the square root of 50 is not equal to three times the square root of 10.
Explanation:No, Aaron is not correct. The length of the diagonal of the blue tablecloth is not three times the length of the diagonal of the red tablecloth. This is because the square root of 50 (√50) is not equal to three times the square root of 10 (3 * √10). In reality, the square root of 50 is approximately 7.07 and three times the square root of 10 is approximately 9.49.
Indeed:√50 ≈ 7.07 and 3 * √10 ≈ 9.49. These are not the same, hence Aaron's claim is incorrect.
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Millennium Liquors is a wholesaler of sparkling wines. Its most popular product is the French Bete Noire, which is shipped directly from France. Weekly demand is 50 cases. Millennium purchases each case for $110, there is a $350 fixed cost for each order (independent of the quantity ordered), and its annual holding cost is 25 percent.
Answer:
economic order quantity is 258 cases per purchase
Step-by-step explanation:
The economic or quantity (EOQ) is the ideal order quantity that should be purchased in order to minimize costs.
Q = √(2DS / H)
D = annual demand in unitsS = order cost per purchase orderH = holding cost per unit, per yearD = 50 cases x 52 weeks = 2,600 cases per year
S = $350 per purchase order
H = $110 x 25% = $27.50
Q = √[(2 x 2,600 x 350) / 27.50] = √(1,820,000 / 27.5) = √66,181.82 = 257.26 cases ≈ 258 cases
Final answer:
The economic order quantity is 258 cases per purchase
Explanation:
The question pertains to the economic order quantity (EOQ) model in business operations and supply chain management, specifically in the context of a wholesaler dealing with inventory of sparkling wines.
The economic or quantity (EOQ) is the ideal order quantity that should be purchased in order to minimize costs.
[tex]Q = \sqrt{(2DS / H)[/tex]
Where,
D = annual demand in units
S = order cost per purchase order
H = holding cost per unit, per year
D = 50 cases x 52 weeks = 2,600 cases per year
S = $350 per purchase order
H = $110 x 25% = $27.50
Q = [tex]\sqrt{[(2 x 2,600 x 350) / 27.50][/tex]
[tex]= \sqrt{(1,820,000 / 27.5)[/tex]
= [tex]\sqrt{66,181.82[/tex]
= 257.26 cases
= 258 cases
HELP QUICK PLEASE
The perimeter is 116 in and the width is 27 in.
What's the length?
Answer:
31
Step-by-step explanation:
116 - 27 -27 = 62 / 2 = 31
Answer:
The length is 31 in
Step-by-step explanation:
Perimeter = 2(Length + width)
say p = perimeter, l = length and w = width
perimeter = 166, w = 27
166 = 2(l + 27)
116 = 2l + 2×27
2l + 54 = 116
2l = 116 - 54
2l = 62
l = 62/2
l = 31 in
say
The sales of a grocery store had an average of $8,000 per day. The store introduced several advertising campaigns in order to increase sales. To determine whether or not the advertising campaigns have been effective in increasing sales, a sample of 64 days of sales was selected. It was found that the average was $8,250 per day. From past information, it is known that the standard deviation of the population is $1,200.
The value of the test statistic is:_________.
Answer:
The value of the test statistic is 1.667
Step-by-step explanation:
We are given that the sales of a grocery store had an average of $8,000 per day. The store introduced several advertising campaigns in order to increase sales. For this a random sample of 64 days of sales was selected. It was found that the average was $8,250 per day. From past information, it is known that the standard deviation of the population is $1,200.
We have to determine whether or not the advertising campaigns have been effective in increasing sales.
Let, Null Hypothesis, [tex]H_0[/tex] : [tex]\mu[/tex] = $8,000 {means that the advertising campaigns have not been effective in increasing sales}
Alternate Hypothesis, [tex]H_1[/tex] : [tex]\mu[/tex] > $8,000 {means that the advertising campaigns have been effective in increasing sales}
The test statistics that will be used here is One sample z-test statistics;
T.S. = [tex]\frac{Xbar-\mu}{\frac{\sigma}{\sqrt{n} } }[/tex] ~ N(0,1)
where, Xbar = sample mean = $8,250
[tex]\sigma[/tex] = population standard deviation = $1,200
n = sample size = 64
So, test statistics = [tex]\frac{8,250-8,000}{\frac{1,200}{\sqrt{64} } }[/tex]
= 1.667
Therefore, the value of test statistics is 1.667 .
Pepsi and Mountain Dew products sponsored a contest giving away a Lamborghini sports car worth $215,000. The probability of winning from a single bottle purchase was .00000884. Find the expected value. (Round your answer to 4 decimal places.) Expected value $
Answer:
$1.9006
Step-by-step explanation:
The expected value out of an event with value v and the probability p of that event to happen is the product of the value v and the probability p itself.
Therefore, the expected value of winning $215000 with probability of 0.00000884 bottle purchase is
E = pv = 215000 * 0.00000884 = $1.9006
The expected value, multiplied by the chance of winning the Lamborghini, is approximately $1.9004. This value means that if you could repeat this contest over and over, on average, you would gain about $1.90 per bottle purchased.
Explanation:The subject of this question is about the expected value in probability. In the given scenario, when a Pepsi or Mountain Dew bottle is purchased, there's a probability of .00000884 of winning a Lamborghini sports car worth $215,000.
The expected value is calculated as the product of the value of the prize and the probability of winning it. Therefore, the expected value for this case would be (215000*.00000884) which equals to $1.9004, rounded to 4 decimal places. However, in the previous calculation, there was an error, resulting in a negative value which should not be the case in this context.
Expected value offers a predicted value of a variable, calculated as the sum of all possible values each multiplied by the probability of its occurrence. It is widely used in Probability Theory and Statistics.
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Question 3 This questions requires you to examine computational differences for methods used to calculate sample variation. You will implement three approaches. You should find that two of these approaches calculate the sample variation more accurately than the other approach. Note that the values provided in part a. coincide with a large mean and a small variance. This scenario can be particularly problematic computationally when calculating sample variance. a. Add code to H4_Q3 that declares an array of doubles named values initialized with the following: {100000000.6,99999999.8,100000002.8,99999998.5,100000001.3 }. b. Add code to H4_Q3 that determines the sample variance using the following equation: S = Pn−1 i=0 (xi − x¯) 2 n − 1 where x¯ = Pn−1 i=0 xi n . The individual xi values are given as {10,000.6, 9,999.8, 10,002.8, 9,998.5, 10,001.3 } so that n = 5 with x indexed as i = 0, . . . , 4. c. Add code to H4_Q3 that determines the sample variance using the following equation: 2 S = Pn−1 i=0 x 2 i n − Pn−1 i=0 xi n !2 × n n − 1 with xi given in b. d. Add code to H4_Q3 that calculates the sample variance using the following method: Algorithm 1: Sample Variance Algorithm: Part d Result: Sample Variance: Sn−1 n−1 initialization: Set M0 = x0; S0 = 0 and i = 1; while i ≤ n − 1 do Mi = Mi−1 + xi−Mx−1 i+1 ; Si = Si−1 + (xk − Mk−1) ∗ (xk − Mk) end with xi given in b. This approach to calculating sample variance is known as the Welford method.
Answer:
sigma formulas are executed by using for loop to sum all the values.
public class H4_Q3{
public static void main(String[] args)
{
//Part a
double[] values = {100000000.6, 99999999.8, 100000002.8, 99999998.5, 100000001.3};
int n = values.length;
//Part b;
double sum = 0;
double sample_average = 0;
double sample_variance = 0;
int i = 0;
for(i = 0; i < n; i++)
{
sum = sum + values[i];
}
sample_average = sum/n;
for(i = 0; i < n; i++)
{
sample_variance = sample_variance + (Math.sqrt(values[i]) - sample_average);
}
System.out.println("Sample variance (Part b formula): "+sample_variance);
//Part c
double sum_squared = 0;
double sum_values = sample_average;
for(i = 0; i < n; i++)
{
sum_squared = sum_squared + Math.sqrt(values[i]);
}
sum_squared = sum_squared/n;
sample_variance = (sum_squared - Math.sqrt(sum_values)) * (n/ (n - 1));
System.out.println("Sample variance (Part c formula): "+sample_variance);
//Part d
sample_variance = 0;
double[] M = new double[n];
double[] S = new double[n];
M[0] = values[0];
S[0] = 0;
i = 1;
while(i < n)
{
M[i] = M[i-1] + ((values[i] - M[i-1])/i+1);
S[i] = S[i-1] + (values[i] - M[i-1]) * (values[i] - M[i]);
i++;
}
System.out.println("Sample variance (Part d formula): "+S[n-1]/n);
}
}
3.30 Survey response rate. Pew Research reported in 2012 that the typical response rate to their surveys is only 9%. If for a particular survey 15,000 households are contacted, what is the probability that at least 1,500 will agree to respond
Answer:
0% probability that at least 1,500 will agree to respond
Step-by-step explanation:
I am going to use the binomial approximation to the normal to solve this question.
Binomial probability distribution
Probability of exactly x sucesses on n repeated trials, with p probability.
Can be approximated to a normal distribution, using the expected value and the standard deviation.
The expected value of the binomial distribution is:
[tex]E(X) = np[/tex]
The standard deviation of the binomial distribution is:
[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]
Normal probability distribution
Problems of normally distributed samples can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
When we are approximating a binomial distribution to a normal one, we have that [tex]\mu = E(X)[/tex], [tex]\sigma = \sqrt{V(X)}[/tex].
In this problem, we have that:
[tex]n = 15000, p = 0.09[/tex]
So
[tex]\mu = E(X) = np = 15000*0.09 = 1350[/tex]
[tex]\sigma = \sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{15000*0.09*0.91} = 35.05[/tex]
What is the probability that at least 1,500 will agree to respond
This is 1 subtracted by the pvalue of Z when X = 1500-1 = 1499. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{1499 - 1350}{35.05}[/tex]
[tex]Z = 4.25[/tex]
[tex]Z = 4.25[/tex] has a pvalue of 1.
1 - 1 = 0
0% probability that at least 1,500 will agree to respond
The probability that at least 1,500 will agree to respond is 0.000009.
How to calculate the probabilityFrom the information given,
n = 15000
p = 0.09
Therefore, np = 15000 × 0.09
= 1350
nq = 15000 × (0.91)
= 13650
The probability that at least 1,500 will agree to respond will be:
= 1 - P (Z < (1500 - 1350)/35.05]
= 1 - P(Z < 4.2796)
= 0.000009
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Suppose the area that can be painted using a single can of spray paint is slightly variable and follows a nearly normal distribution with a mean of 25 square feet and a standard deviation of 3 square feet.
(a) What is the probability that the area covered by a can of spray paint is more than 27 square feet?
(b) Suppose you want to spray paint an area of 540 square feet using 20 cans of spray paint. On average, how many square feet must each can be able to cover to spray paint all 540 square feet?
(c) What is the probability that you can cover a 540 square feet area using 20 cans of spray paint?
(d) If the area covered by a can of spray paint had a slightly skewed distribution, could you still calculate the probabilities in parts (a) and (c) using the normal distribution?
Answer:
Step-by-step explanation:
Hello!
You have the variable
X: Area that can be painted with a can of spray paint (feet²)
The variable has a normal distribution with mean μ= 25 feet² and standard deviation δ= 3 feet²
since the variable has a normal distribution, you have to convert it to standard normal distribution to be able to use the tabulated accumulated probabilities.
a.
P(X>27)
First step is to standardize the value of X using Z= (X-μ)/ δ ~N(0;1)
P(Z>(27-25)/3)
P(Z>0.67)
Now that you have the corresponding Z value you can look for it in the table, but since tha table has probabilities of [tex]P(Z<Z_{\alpha })[/tex], you have to do the following conervertion:
P(Z>0.67)= 1 - P(Z≤0.67)= 1 - 0.74857= 0.25143
b.
There was a sample of 20 cans taken and you need to calculate the probability of painting on average an area of 540 feet².
The sample mean has the same distribution as the variable it is ariginated from, but it's variability is affected by the sample size, so it has a normal distribution with parameners:
X[bar]~N(μ;δ²/n)
So the Z you have to use to standardize the value of the sample mean is Z=(X[bar]-μ)/(δ/√n)~N(0;1)
To paint 540 feet² using 20 cans you have to paint around 540/20= 27 feet² per can.
c.
P(X≤27) = P(Z≤(27-25)/(3/√20))= P(Z≤2.98)= 0.999
d.
No. If the distribution is skewed and not normal, you cannot use the normal distribution to calculate the probabilities. You could use the central limit theorem to approximate the sampling distribution to normal if the sample size was 30 or grater but this is not the case.
I hope it helps!
AX and EX are secant segments that intersect at point X. Circle C is shown. Secants A X and E X intersect at point X outside of the circle. Secant A X intersects the circle at point B and secant E X intersects the circle at point E. The length of A B is 7, the length of B X is 2, and the length of X D is 3. What is the length of DE? 1 unit 3 units 4One-half units 4Two-thirds units
Answer:
DE = 3 units
Step-by-step explanation:
The image is attached.
There are 2 secant lines in the circle. We can use secant theorem to solve this easily.
It states that "if 2 secants are drawn to a circle from an outside point, then product of 1 secant and its "outside" part is equal to product of other secant and its "outside" part.
From the figure, we can say:
AX * BX = EX * DX
We let the length to find , DE, be "x".
Thus, we can write:
[tex]AX * BX = EX * DX\\(7+2)(2)=(x+3)(3)[/tex]
Now, we solve this for x:
[tex](7+2)(2)=(x+3)(3)\\(9)(2)=(3)(x+3)\\18=3x+9\\3x=18-9\\3x=9\\x=3[/tex]
Thus,
DE = 3 units
Answer:
the answer is b 3 units
Step-by-step explanation:
For ANOVA, the test statistic is called an ____ test statistic (also called a ____-ratio), which is the variance (2) samples (a.k.a., variation due to treatment) divided by the variance (3) samples (a.k.a., variation due to error or chance).
The test statistic for ANOVA is called an F test statistic (or F-ratio), which is calculated by dividing the variance between the samples by the variance within the samples.
Explanation:The test statistic for ANOVA is called an F test statistic (also called an F-ratio). It is calculated by dividing the variance between the samples (variation due to treatment) by the variance within the samples (variation due to error or chance).
The F statistic follows an F distribution with (number of groups - 1) as the numerator degrees of freedom and (number of observations - number of groups) as the denominator degrees of freedom.
For ANOVA (Analysis of Variance), the test statistic is called an F test statistic (also called an F-ratio), which is the variance between samples (a.k.a., variation due to treatment) divided by the variance within samples (a.k.a., variation due to error or chance).
Fill in blank (2): between, Fill in blank (3): within
Analysis of Variance (ANOVA)
ANOVA is a statistical method used to compare the means of three or more samples to see if at least one of them is significantly different from the others. It does this by analyzing the variances within the data.
F-Test Statistic
The test statistic used in ANOVA is called the F-test statistic or the F-ratio. This F-ratio helps to determine whether the variances between the sample means are significantly larger than the variances within the samples. The F-ratio is calculated as follows:
[tex]\[ F = \frac{\text{variance between samples}}{\text{variance within samples}} \][/tex]
Variance Between Samples
The variance between samples (also known as between-group variance or treatment variance) measures the variability among the sample means. This variability reflects how much the group means differ from the overall mean. If the group means are very different from each other, the between-group variance will be large. This part of the variance is often attributed to the effect of the different treatments or conditions being compared.
- Blank (2): The term used here is between.
Variance Within Samples
The variance within samples (also known as within-group variance or error variance) measures the variability within each of the groups. This variability reflects how much the individual data points within each group differ from their respective group mean. This part of the variance is usually attributed to random error or chance.
- Blank (3): The term used here is within.
In the context of ANOVA:
- The F-test statistic (F-ratio) is used to compare the variance between samples to the variance within samples.
- The variance between samples represents the variation due to treatment.
- The variance within samples represents the variation due to error or chance.
The complete question is
For ANOVA, the test statistic is called an_ test statistic (also called an_-ratio), which is the variance (2) samples (a.k.a., variation due to treatment) divided by the variance _(3)_samples (a.k.a., variation due to error or chance) The first two blanks are completed with the letter this author uses for the ANOVA test statistic. What is this letter? Fill in blank (2): Fill in blank (3)
What are the solutions of x2 +6x-6= 10?
OX=-11 or x= 1
OX=-11 or x=-1
O X=-8 or X=-2
O X =-8 or x=2
Answer:
x = 1 ,or x = -7
Obviously, the true answer is not in the options given.
Step-by-step explanation:
x² + 6x - 6 = 10
The above equation can not be factorized, hence the use of Almighty Formula.
x = [-b +- √b² - 4ac] / 2a
Where a = 1, b = 6, c = -6
x = [-6 +- √6² - (4*1*-6)] / 2*1
x = [-6 +- √36 - (-24)] / 2
x = [-6 +- √36 + 24] / 2
x = [-6 +- √60] / 2
x = [-6 +- 7.75] / 2
x = [-6 + 7.75] / 2 ,or x = [-6 - 7.75] / 2
x = 1.75/2 ,or x = -13.75/2
x = 0.875 ,or x = -6.875
Approximately
x = 1 ,or x = -7
Answer:D
Step-by-step explanation:
A communication channel transmits a signal as sequence of digits 0 and 1. The probability of incorrect reception of each digit is p. To reduce the probability of error at reception, 0 is transmitted as 00000 (five zeroes) and 1, as 11111. Assume that the digits are received independently and the majority decoding is used. Compute the probability of receiving the signal incorrectly if the original signal is (a) 0; (b) 101. Evaluate the probabilities when p D 0:2.
Answer:
Probability of receiving the signal incorrectly is ".05792"
Step-by-step explanation:
Since it is mentioned here that the majority decoding is used so it implies that if the message is decoded as zero if there have been minimum of 3 Zeros in the messgae.
As we can see that there have been 5 bits, so the incorrection will occur only if there have been atleast 3 incorrect bits. Here we are asked to find out the probability of receiveing the signal incorrectly so i will take incorrectly transmiited bit as "Success".
The binomial distribution gives the probability of exactly m successes in n trials where the probability of each individual trial succeeding is p.
With this method, we get the following pattern,
Binomial at (m=3, n=5, p=0.2) for probability of incorrection due to exactly 3 fails,
Binomial at (m=4, n=5, p=0.2) for probability of incorrection due to exactly 4 fails,
Binomial at (m=5 ,n=5, p=0.2) for probability of incorrection due to exactly 5 fails.
hence the probability "P" of receiving the signal incorrectly will be,
P=(⁵₃) p³ (1 − p)⁵⁻³ + (⁵₄) p⁴(1 − p)⁴⁻³ + (⁵₅) p³(1 − p)³⁻³
whereas,
(⁵₃)= 5! / (5-3)! = 10
(⁵₄)= 5! / (5-4)! = 5
(⁵₅)= 5! / (5-5)! = 1
Putting these values in above equation we get,
P= 10 (0.2)³(1-0.2)² + 5(0.2)⁴(1-0.2)¹ + (0.2)⁵
P=.05792
So the probablility "P" of receiving the signal incorrectly becomes ".05792"
The TurDuckEn restaurant serves 8 entr´ees of turkey, 12 of duck, and 10 of chicken. If customers select from these entr´ees randomly, what is the probability that exactly two of the next four customers order turkey entr´ees?
Answer:
The probability that exactly 2 of the next four customers order turkey entries is 6 * 0.0393359 = 0.2360
Step-by-step explanation:
There are a total of 8+12+10 = 30 entries, 8 of them being turkey. Lets compute the probability that the first 2 customers order turkey entries and the remaining 2 do not.
For the first customer, he has 8 turkey entries out of 30, so the probability for him to pick a turkey entry is 8/30. For the second one there will be 29 entries left, 7 of them being turkey. So the probability that he picks a turkey entry is 7/29. The third one has 28 entries left, 6 of them which are turkey and 22 that are not. The probability that he picks a non turkey entry is 22/28. And for the last one, the probability that he picks a non turkey entry is 21/27. So the probability of this specific event is
8/30*7/29*22/28*21/27 = 0.0393359
Any other event based on a permutation of this event will have equal probability (we are just swapping the order of the numerators when we permute). The total number of permutations is 6, and since each permutation has equal probability, then the probability that exactly 2 of the next four customers order turkey entries is 6 * 0.0393359 = 0.2360