Answer:
1/2
Step-by-step explanation:
well imagine there are only 2 people who has a laptop or phone. so it would be 1/2 because there are 2 people with a laptop and phone, and they are asking who uses a cell phone to stay connected which is 1.
The number of surface flaws in plastic panels used in the interior of automobiles has a Poisson distribution with a mean of 0.06 flaws per square foot of plastic panel. Assume an automobile interior contains 10 square feet of plastic panel. (a) What is the probability that there are no surface flaws in an auto's interior
Answer:
There is a 54.88% probability that there are no surface flaws in an auto's interior.
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
[tex]e = 2.71828[/tex] is the Euler number
[tex]\mu[/tex] is the mean in the given interval.
The number of surface flaws in plastic panels used in the interior of automobiles has a Poisson distribution with a mean of 0.06 flaws per square foot of plastic panel. Assume an automobile interior contains 10 square feet of plastic panel.
For one square foot, we have 0.06 flaws.
So for 10 square feet, the mean is [tex]\mu = 10*0.06 = 0.6[/tex]
(a) What is the probability that there are no surface flaws in an auto's interior
This is P(X = 0).
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
[tex]P(X = 0) = \frac{e^{-0.6}*(0.6)^{0}}{(0.6)!} = 0.5488[/tex]
There is a 54.88% probability that there are no surface flaws in an auto's interior.
The starting salaries of individuals with an MBA degree are normally distributed with a mean of $40,000 and a standard deviation of $5,000.What is the probability that a randomly selected individual with an MBA degree will get a starting salary of at least $30,000?1) 0.97722) 0.50003) 0.99874) 0.0228
Answer:
1) 0.9772
Step-by-step explanation:
Problems of normally distributed samples are 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.
In this problem, we have that:
[tex]\mu = 40000, \sigma = 5000[/tex]
What is the probability that a randomly selected individual with an MBA degree will get a starting salary of at least $30,000?
This is 1 subtracted by the pvalue of Z when X = 30000. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{30000 - 40000}{5000}[/tex]
[tex]Z = -2[/tex]
[tex]Z = -2[/tex] has a pvalue of 0.0228.
1 - 0.0228 = 0.9772
0.9772 that a randomly selected individual with an MBA degree will get a starting salary of at least $30,000
Final answer:
Using the normal distribution, the probability that a randomly selected individual with an MBA degree will get a starting salary of at least $30,000 is approximately 0.9772.
Explanation:
The probability of a randomly selected individual with an MBA degree getting a starting salary of at least $30,000 is determined using the normal distribution with a mean of $40,000 and a standard deviation of $5,000. You calculate the z-score for $30,000, which is (30,000 - 40,000) / 5,000 = -2.
Then, you look this z-score up in the standard normal distribution table (or use a calculator equipped with normal distribution functions) to find the probability of getting a value greater than -2. This probability corresponds to the area to the right of the z-score, which is essentially 1 minus the cumulative probability up to the z-score.
According to standard normal distribution tables, the cumulative probability of a z-score of -2 is approximately 0.0228. Therefore, the probability of getting at least $30,000 is
1 - 0.0228, which equals approximately 0.9772.
Comparing this to available choices, option 1) 0.9772 is the correct answer.
I'll mark you brainliest if you help me ASAP!
Two numbers total 63 and have a difference of 11. Find the two numbers.
Answer:
The two numbers are 37 and 26.
Step-by-step explanation:
This question can be solved by a simple system of equations.
Building the system:
I am going to say that our numbers are x and y.
Two numbers total 63
This means that [tex]x + y = 63[/tex]
difference of 11
This means that [tex]x - y = 11[/tex].
Solving the system
[tex]x + y = 63[/tex]
[tex]x - y = 11[/tex]
Using the addition method
x + x + y - y = 63 + 11
2x = 74
x = 37
[tex]x - y = 11[/tex]
[tex]y = x - 11[/tex]
[tex]y = 37 - 11 = 26[/tex]
The two numbers are 37 and 26.
Answer:
The total 2 numbers are 37 and 26
hope i helped
what would 20% of 1,500 be?
Answer:
300
Step-by-step explanation:
20% of 1,500 = 300
(Source: Google)
Answer:
300
Step-by-step explanation:
1. Consider an athlete running a 40-m dash. The position of the athlete is given by , where d is the position in meters and t is the time elapsed, measured in seconds. Compute the average velocity of the runner over the given time intervals. a. b. c. d. e. Use the preceding answers to guess the instantaneous velocity of the runner at sec. ( ) 3 4 6 t dt t = + [1.95, 2.05] [1.995, 2.005] [1.9995, 2.0005] [2, 2.00001] t = 2
There is some information missing in the question, since we need to know what the position function is. The whole problem should look like this:
Consider an athlete running a 40-m dash. The position of the athlete is given by [tex]d(t)=\frac{t^{2}}{6}+4t[/tex] where d is the position in meters and t is the time elapsed, measured in seconds.
Compute the average velocity of the runner over the intervals:
(a) [1.95, 2.05]
(b) [1.995, 2.005]
(c) [1.9995, 2.0005]
(d) [2, 2.00001]
Answer
(a) 6.00041667m/s
(b) 6.00000417 m/s
(c) 6.00000004 m/s
(d) 6.00001 m/s
The instantaneous velocity of the athlete at t=2s is 6m/s
Step by step Explanation:
In order to find the average velocity on the given intervals, we will need to use the averate velocity formula:
[tex]V_{average}=\frac{d(t_{2})-d(t_{1})}{t_{2}-t_{1}}[/tex]
so let's take the first interval:
(a) [1.95, 2.05]
[tex]V_{average}=\frac{d(2.05)-d(1.95)}{2.05-1.95}[/tex]
we get that:
[tex]d(1.95)=\frac{(1.95)^{3}}{6}+4(1.95)=9.0358125[/tex]
[tex]d(2.05)=\frac{(2.05)^{3}}{6}+4(2.05)=9.635854167[/tex]
so:
[tex]V_{average}=\frac{9.6358854167-9.0358125}{2.05-1.95}=6.00041667m/s[/tex]
(b) [1.995, 2.005]
[tex]V_{average}=\frac{d(2.005)-d(1.995)}{2.005-1.995}[/tex]
we get that:
[tex]d(1.995)=\frac{(1.995)^{3}}{6}+4(1.995)=9.30335831[/tex]
[tex]d(2.005)=\frac{(2.005)^{3}}{6}+4(2.005)=9.363335835[/tex]
so:
[tex]V_{average}=\frac{9.363335835-9.30335831}{2.005-1.995}=6.00000417m/s[/tex]
(c) [1.9995, 2.0005]
[tex]V_{average}=\frac{d(2.0005)-d(1.9995)}{2.0005-1.9995}[/tex]
we get that:
[tex]d(1.9995)=\frac{(1.9995)^{3}}{6}+4(1.9995)=9.33033358[/tex]
[tex]d(2.0005)=\frac{(2.0005)^{3}}{6}+4(2.0005)=9.33633358[/tex]
so:
[tex]V_{average}=\frac{9.33633358-9.33033358}{2.0005-1.9995}=6.00000004m/s[/tex]
(d) [2, 2.00001]
[tex]V_{average}=\frac{d(2.00001)-d(2)}{2.00001-2}[/tex]
we get that:
[tex]d(2)=\frac{(2)^{3}}{6}+4(2)=9.33333333[/tex]
[tex]d(2.00001)=\frac{(2.00001)^{3}}{6}+4(2.00001)=9.33339333[/tex]
so:
[tex]V_{average}=\frac{9.33339333-9.33333333}{2.00001-2}=6.00001m/s[/tex]
Since the closer the interval is to 2 the more it approaches to 6m/s, then the instantaneous velocity of the athlete at t=2s is 6m/s
The average velocity is computed for each interval using the average velocity formula and the given position function, d(t) = 3t^2 + 4t + 6. Instantaneous velocity is calculated by differentiating the position function and substituting the given time point.
Explanation:To find the average velocity, we need to use the formula: average velocity = (final position - initial position) / (final time - initial time). For the position function given, d(t) = 3t^2 + 4t + 6, substitute the time values given in the intervals to find the position at those times, then use those values to calculate the average velocity.
For example, for the first interval [1.95, 2.05], d(1.95) = 3*(1.95)^2 + 4*1.95 + 6 and d(2.05) = 3*(2.05)^2 + 4*2.05 + 6. Subtract these position values and the time values then divide the result.
The instantaneous velocity is calculated by taking the slope of the tangent line at the specified point on the position vs time curve, which is found using the derivative of the position function. The derivative of d(t) = 3t^2 + 4t + 6 is d'(t) = 6t + 4. So, at t = 2, the instantaneous velocity would be d'(2) = 6*2 + 4.
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Mr. Rosenbloom uses 500 ml of gel in his hair every morning. He buys gel in 10 liter bottles. How many days will 1 bottle last.
Answer:
Mr. Rosenbloom 1 bottle of gel will last for 20 days.
Step-by-step explanation:
Given:
Amount of gel used every morning = 500 mL
Amount of gel in 1 bottle = 10 liters.
We need to find the number of days 1 bottle of gel will last for.
Solution:
Now we know that;
1 liter =1000 mL
10 liter = 10000 mL
Now we now that;
500 mL of gel is used = 1 day
10000 mL of gel will be used = Number of days 10000 mL of gel will last.
By Using Unitary method we get;
Number of days 10000 mL of gel will last = [tex]\frac{10000}{500}=20\ days[/tex]
Hence Mr. Rosenbloom 1 bottle of gel will last for 20 days.
For each statement, decide whether descriptive or inferential statistics were used.
a. A resent study showed that eating garlic can lower blood pressure. ___________________
b. The average number of students in a class at White Oak University is 22 _____
Answer:
a. Inferential statistics
b. Descriptive statistics
Step-by-step explanation:
statistics can be categorized into descriptive an inferential statistics. descriptive statistics makes use of a set of data for numerical calculations and provides conclusion based on those numerical calculation. this data could be collected using tables,graphs, and other means of data representation.
Inferential statistics however come up with conclusions and assumptions base on a sample data.
Examples of descriptive statistics are mean, median, mode, quartile, percentile. Thus option B is descriptive.
Option A however is inferential statistics since some assumptions were made based on the effect of garlic on blood pressure.
The standard deviation of pulse rates of adult males is more than 11 bpm. For the random sample of 153 adult males the pulse rate have a standard deviation of 11 .3 bpm. Find the value of the test statistic.
Answer: 160.4040
Step-by-step explanation:
Here , the claim is "The standard deviation of pulse rates of adult males is more than 11 bpm." , i.e. [tex]\sigma>11[/tex]
We use Chi-square test statistic for the test statistic to test the standard deviations :
[tex]\chi^2=\dfrac{(n-1)s^2}{\sigma^2}[/tex] , where s= sample standard deviation , [tex]\sigma[/tex] = population standard deviations and n = sample size.
As per given , n=153 , s= 11.3
Then, Required test statistic will be :
[tex]\chi^2=\dfrac{(153-1)(11.3)^2}{11^2}=\dfrac{152\times127.69}{121}\approx160.4040[/tex]
Hence, the value of the test statistic. = 160.4040
A sociologist studying freshmen carried out a survey, asking, among other questions, how often students went out per week, how many hours they studied per day, and how many hours they slept at night.
The tables provide the answers on the time slept and the time spent studying by whether or not students went out.
Go out Hours/day studied Hours slept less than 6 Hours slept 6 or more Total Stay in dorm Hours/day studied Hours slept less than 6 Hours slept 6 or more Total Less than 2 3 9 12 Less than 2 40 120 160 2 or more 14 14 28 2 or more 20 20 40 Total 17 23 40 Total 60 140 200
When we examine the data, we find that students who studied more slept less, both among those who go out and among those who stay in the dorm.
When we combine both groups of students, we find that those who studied more also slept more.
This is an example of:
a. Simpson's Paradox.
b. Andersen's Paradox.
c. the Probability Paradox.
d. the Gaussian Paradox.
Answer:
This is called Simpson's Paradox.
Therefore the correct option is A.) Simpson's Paradox.
Step-by-step explanation:
i) This is called Simpson's Paradox.
ii) If there are trends that tend to appear in several different groups of data which apparently either disappear or tend to reverse when these data groups are combined.
This is an example of Simpson's Paradox, where a trend appears in different groups of data but disappears or reverses when the groups are combined.
Explanation:This is an example of Simpson's Paradox. Simpson's Paradox occurs when a trend appears in different groups of data but disappears or reverses when the groups are combined. In this case, although students who studied more slept less in both groups (those who went out and those who stayed in the dorm), when the groups are combined, those who studied more also slept more.
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What expression is equivalent to 3•3•3•3
Answer: 3 to the 4 power
Step-by-step explanation:
Answer:
3^4
because it is 3 times it self 4 times
Industrial engineers periodically conduct "work measurement" analyses to determine the time required to produce a single unit of output. At a large processing plant, the number of total worker-hours required per day to perform a certain task was recorded for 50 days. a. Compute the mean, median, and mode of the data set. b. Find the range, variance, and standard deviation of the data set. c. Construct the intervals using the Empirical rule. d. Find the 70th percentile for the data on total daily worker-hours.
Answer:
a) [tex] \bar X =117.8[/tex]
[tex] Median= \frac{117+118}{2}=117.5[/tex]
The mode on this case is the most repeated value 128 with a frequency of 3
b) [tex] Range = Max -Min = 150-88=62[/tex]
[tex] s^2 = 225.334[/tex]
[tex] s= \sqrt{225.334}= 15.011[/tex]
c) [tex] y \pm s[/tex]
[tex] Lower = 117.8 -15.011=102.809[/tex]
[tex] Upper = 117.8 +15.011=132.831[/tex]
[tex] y \pm 2s[/tex]
[tex] Lower = 117.8 -2*15.011=87.797[/tex]
[tex] Upper = 117.8 +2*15.011=147.842[/tex]
[tex] y \pm 3s[/tex]
[tex] Lower = 117.8 -3*15.011=72.787[/tex]
[tex] Upper = 117.8 +3*15.011=162.85[/tex]
d) For this case we can calculate the position where we have accumulated 70% of the data below.
50*0.7 = 35
So on the position 35th from the dataset ordered we see that the value is 128 and this value would represent the 70th percentile on this case.
Step-by-step explanation:
For this case we consider the following data:
128,119,95,97,124,128,142,98,108,120,113,109,124,132,97,138,133,136,120,112,146,128,103,135,114,109,100,111,131,113,124,131,133,131,88,118,116,98,112,138,100,112,111,150,117,122,97,116,92,122
Part a
For this case we can calculate the mean with the following formula:
[tex] \bar X = \frac{\sum_{i=1}^{50} X_i}{50}[/tex]
And after replace we got [tex] \bar X =117.8[/tex]
In order to calculate the median first we order the dataset and we got:
88 92 95 97 97 97 98 98 100 100 103 108 109 109 111 111 112 112 112 113 113 114 116 116 117 118 119 120 120 122 122 124 124 124 128 128 128 131 131 131 132 133 133 135 136 138 138 142 146 150
The median would be the average between the position 25 and 26 from the data ordered and we got:
[tex] Median= \frac{117+118}{2}=117.5[/tex]
The mode on this case is the most repeated value 128 with a frequency of 3
Part b
the range is defined as the difference between the maximun and minimum so we got:
[tex] Range = Max -Min = 150-88=62[/tex]
The sample variance can be calculated with this formula:
[tex] s^2 = \frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}[/tex]
And after calculate we got: [tex] s^2 = 225.334[/tex]
And the deviation is just the square root of the variance and we got:
[tex] s= \sqrt{225.334}= 15.011[/tex]
Part c
For this case we can construct the interval with 1 , 2 and 3 deviation from the mean like this:
[tex] y \pm s[/tex]
[tex] Lower = 117.8 -15.011=102.809[/tex]
[tex] Upper = 117.8 +15.011=132.831[/tex]
[tex] y \pm 2s[/tex]
[tex] Lower = 117.8 -2*15.011=87.797[/tex]
[tex] Upper = 117.8 +2*15.011=147.842[/tex]
[tex] y \pm 3s[/tex]
[tex] Lower = 117.8 -3*15.011=72.787[/tex]
[tex] Upper = 117.8 +3*15.011=162.85[/tex]
Part d
For this case we can calculate the position where we have accumulated 70% of the data below.
50*0.7 = 35
So on the position 35th from the dataset ordered we see that the value is 128 and this value would represent the 70th percentile on this case.
Suppose that a ball is dropped from the upper observation deck of the CN Tower in Toronto, 450 m above the ground. Find the velocity of the ball after 3 seconds. SOLUTION Through experiments carried out four centuries ago, Galileo discovered that the distance fallen by any freely falling body is proportional to the square of the time it has been falling. (This model for free fall neglects air resistance.) If the distance fallen after t seconds is denoted by s(t) and measured in meters, then Galileo's law is expressed by the equation s(t) = 4.9t2. The difficulty in finding the velocity after 3 s is that we are dealing with a single instant of time (t = 3), so no time interval is involved. However, we can approximate the desired quantity by computing the average velocity over the brief time interval of a tenth of a second from t = 3 to t = 3.1: average velocity = change in position time elapsed = s(3.1) − s(3) 0.1 = 4.9 2 − 4.9 2 0.1 = m/s. The table shows the results of similar calculations of the average velocity over successively smaller time periods. It appears that as we shorten the time period, the average velocity is becoming closer to m/s (rounded to one decimal place). The instantaneous velocity when t = 3 is defined to be the limiting value of these average velocities over shorter and shorter time periods that start at t = 3. Thus the (instantaneous) velocity after 3 s is the following. (Round your answer to one decimal place.) v = m/s
The velocity of the ball after 3 seconds will be 29.43 meters per second.
What is Algebra?The analysis of mathematical representations is algebra, and the handling of those symbols is logic.
Suppose that a ball is dropped from the upper observation deck of the CN Tower in Toronto, 450 m above the ground.
Then the velocity of the ball after 3 seconds will be given as,
We know that the first equation of motion.
v = u - gt
Where v is the final velocity, u is the initial velocity, g is the acceleration due to gravity, and t is the time in seconds. Then we have
v = 0 - 9.81 x 3
v = -29.43 m/s
The velocity of the ball after 3 seconds will be 29.43 meters per second.
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Final answer:
The velocity of the ball after 3 seconds can be found using Galileo's law of free fall. By calculating the average velocity over a brief time interval, we can approximate the instantenous velocity. The velocity of the ball after 3 seconds is therefore m/s.
Explanation:
The velocity of the ball after 3 seconds can be found using Galileo's law of free fall. According to the given information, the distance fallen after t seconds is given by the equation s(t) = 4.9t², where s(t) is the distance fallen in meters and t is the time in seconds. To find the velocity, we can approximate it by computing the average velocity over a brief time interval. We can calculate the average velocity from t = 3 to t = 3.1 by finding the change in position divided by the time elapsed. Plugging the values into the equation, we get:
Average velocity = (s(3.1) - s(3)) / 0.1 = (4.9(3.1)² - 4.9(3)²) / 0.1 = m/s
Therefore, the velocity of the ball after 3 seconds is m/s, rounded to one decimal place.
Delta Airlines quotes a flight time of 2 hours, 5 minutes for its flights from Cincinnati toTampa. Suppose we believe that actual flight times are uniformly distributed between 2 hours and 2 hours, 20 minutes.
a. Show the graph of the probability density function for flight time.b. What is the probability that the flight will be no more than 5 minutes late?c. What is the probability that the flight will be more than 10 minutes late?d. What is the expected flight time?
Answer:
a) Figure attached
b) [tex] P(X<130 min)= F(130) = \frac{130-120}{20}=0.5[/tex]
c) [tex] P(X>135) =1-P(X<135) = 1- F(135) = 1- \frac{135-120}{20}= 0.25[/tex]
d) [tex] E(X) =\frac{a+b}{2}= \frac{120+140}{2}= 130min[/tex]
Step-by-step explanation:
2 hr = 120 min
2hr 20 min = 120+20 = 140 min
Let X the random variable that represent "flight time". And we know that the distribution of X is given by:
[tex]X\sim Uniform(120 ,140)[/tex]
For this case the density function for A is given by:
[tex] f(X) = \frac{1}{b-a}= \frac{1}{20} , 120\leq X \leq 140 [/tex]
And [tex] f(X)= 0[/tex] for other case
Part a
For this case we can see the figure attached. We see that the probability density function is defined between 120 and 140 minutes.
Part b
The arrival time is 2hr 5 min = 125 min. So then 5 minutes leate means 130 min
For this case we want to find this probability:
[tex] P(X<130 min)[/tex]
And we can use the cumulative distribution function for X given by:
[tex] F(X) = \frac{x-120}{140-120} = \frac{x-120}{20} , 120\leq X \leq 140 [/tex]
And if we use this formula we got:
[tex] P(X<130 min)= F(130) = \frac{130-120}{20}=0.5[/tex]
Part c
For this case more than 10 minutes late means 125 +10 = 135 min or more, so we want this probability:
[tex] P(X>135)[/tex]
And using the complement rule we have:
[tex] P(X>135) =1-P(X<135) = 1- F(135) = 1- \frac{135-120}{20}= 0.25[/tex]
Part d
The expected value for the uniform distribution is given by:
[tex] E(X) =\frac{a+b}{2}= \frac{120+140}{2}= 130min[/tex]
"There are 15 questions on an exam. In how many ways can the exam be answered with exactly 8 answers correct?"
Answer:
The exam can be answered with exactly 8 answers correct in 6435 ways.
Step-by-step explanation:
The order is not important.
For example, answering correctly the questions 1,2,3,4,5,6,7,8 is the same outcome as answering 2,1,3,4,5,6,7,8. So we use the combinations formula to solve this problem.
Combinations formula:
[tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
"There are 15 questions on an exam. In how many ways can the exam be answered with exactly 8 answers correct?"
Combinations of 8 questions from a set of 15. So
[tex]C_{15,8} = \frac{15!}{8!(15-8)!} = 6435[/tex]
The exam can be answered with exactly 8 answers correct in 6435 ways.
To find the number of ways to answer 15 exam questions with exactly 8 correct answers, you use the binomial coefficient formula. The calculation yields 15C8 = 6,435. Thus, there are 6,435 ways to answer the exam with 8 correct answers.
The formula for finding the number of ways to choose k items from n items is given by:
nCk = n! / [k!(n-k)!]
In this case, we need to find the number of ways to get exactly 8 correct answers out of 15 questions:
n = 15 (total questions)k = 8 (correct answers)Plugging these values into the formula, we get:
15C8 = 15! / [8!(15-8)!]
Which simplifies to:
15C8 = 15! / (8! * 7!)
Calculating the factorial values:
15! = 15 × 14 × 13 × 12 × 11 × 10 × 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 18! = 8 × 7 × 6 × 5 × 4 × 3 × 2 × 17! = 7 × 6 × 5 × 4 × 3 × 2 × 1By cancelling out the common terms, we get:
15C8 = (15 × 14 × 13 × 12 × 11 × 10 × 9) / (7 × 6 × 5 × 4 × 3 × 2 × 1) = 6435
Conclusion
There are 6,435 ways to answer the exam with exactly 8 answers correct.
In a field there are cows, birds, and spiders. Spiders have 4 eyes and 8 legs each. In the field there are 20 eyes and 30 legs. All three animals are present, and there is an odd number of each animal. How many spiders, cows, and birds are present?
Answer:
1 spider, 3 cows, 5 birds.
Step-by-step explanation:
Cows (C): 4 legs, 2 eyes.
Birds (B): 2 legs, 2 eyes.
Spiders (S): 8 legs, 4 eyes.
The number of legs and eyes are given, respectively by:
[tex]30 = 4C+2B+8S\\20 = 2C+2B+4S[/tex]
Multiplying the second equation by -2 and adding it to the first one gives us the number of birds:
[tex]30 -40= 4C-4C+2B-4B+8S-8S\\-10 = -2B\\B=5[/tex]
Rewriting the original equations with B =5:
[tex]30 = 4C+2*5+8S\\20 = 2C+2*5+4S\\20 = 4C+8S\\10 = 2C+4S\\C=5-2S[/tex]
Since the number of cows cannot be negative, and both C and S must be odd numbers, the only possible value of S is 1:
[tex]C=5-2S\\S=1\\C=3[/tex]
There are 3 cows, 5 birds, and 1 spider in the field.
To solve this problem, we need to establish equations based on the given information
1. Define Variables
Let c be the number of cows,
b be the number of birds,
and s be the number of spiders
2. Create Equations
The total number of eyes is given to be 20, and knowing that spiders have 4 eyes, birds have 2 eyes, and cows have 2 eyes, we get:
2c + 2b + 4s = 20
Simplifying this, we get:
c + b + 2s = 10 (i)
The total number of legs is given to be 30, with cows having 4 legs, birds having 2 legs, and spiders having 8 legs, we get:
4c + 2b + 8s = 30
Simplifying this, we get:
2c + b + 4s = 15 (ii)
3. Solve Simultaneous Equations
We can subtract equation (i) from (ii):
(2c + b + 4s) - (c + b + 2s) = 15 - 10
c + 2s = 5 (iii)
Substituting (iii) into (i):
(5 - 2s) + b + 2s = 10
5 + b = 10
b = 5;
We know from (iii) that:
c + 2s = 5
Let’s check for odd values for s:
If s = 1, then c = 5 - 2(1) = 3 (valid since cows = 3)
Hence, the solution is:
c = 3, b = 5, s = 1
Checking:
Total eyes = 2(3) + 2(5) + 4(1) = 6 + 10 + 4 = 20 (correct)
Total legs = 4(3) + 2(5) + 8(1) = 12 + 10 + 8 = 30 (correct)
There are 3 cows, 5 birds, and 1 spider in the field.
What is a real life word problem for the equation
y=2x
Answer:
y = 2x
Step-by-step explanation:
Claire is hungry. She buys 2 donuts each costing x $. How much should she pay?
Since one donut costs x $ 2 donuts cost 2x $.
Therefore, total amount Claire should pay, call it y = 2x.
Hence, we have y = 2x.
Final answer:
A real-life word problem for the equation y=2x could be renting a bike at a rate of $2 per hour, in which the cost (y) is proportional to the rental time (x). This scenario shows a linear relationship with the total cost increasing directly with the rental time.
Explanation:
A real-life word problem for the equation y=2x could involve a situation where the cost y (in dollars) to hire a bike is proportional to the number of hours x you rent it for. If it costs $2 per hour to rent a bike, then the total cost is represented by the equation y=2x. For example, renting the bike for 3 hours would cost y=2(3)=6 dollars.
Applying this equation, it follows that as the time of rental increases, the cost increases at a constant rate. This represents a linear relationship between time and cost.
Example Calculation:
Let x represent the time in hours you rent a bike.
The total cost y is twice the rental time (since it's $2 per hour).
To find the cost of renting a bike for 5 hours, substitute x=5 into the equation: y=2(5).
The total cost would be y=$10.
The equation y=2x is used here to model a simple proportional relationship where one variable increases directly as the other does. It does not represent a quadratic, hyperbolic, or any other non-linear relationship.
Two marbles are selected from a bag containing two red marbles, two blue marbles, and one yellow marble. The color of each marble is recorded.
Determine the sample space for the experiment.
Answer:
(a) {RR,BB,RB,RY,BY}
(b) {R1 R2, R1 B1, R1 B2, R1 Y, R2 R1, R2 B1, R2 B2, R2 Y, B1 R1, B1 R2, B1 B2, B1 Y, B2 R1, B2 B1, B2 R2, B2 Y, Y R1, Y R2, Y B1, Y B2}.
Step-by-step explanation:
This question can be answered in two ways :
(a) When order of picking marbles does not matter.
(b) When order of picking marbles does matter.
So, First I will explain what will be the sample space for the experiment when order of picking marbles does not matter.Red marbles in the bag = 2
Blue marbles in the bag = 2
Yellow marbles in the bag = 1
Now since we have to select two marbles from the bag, the sample cases will be:
Both of the marbles could be Red.Both of the marbles could be Blue.One marble is Red and other one is Blue.One marble is Red and other one is Yellow.One marble is Blue and other one is Yellow.In short Sample space = {RR,BB,RB,RY,BY} where R = Red , B = Blue and Y = Yellow.
2. Now I will explain what will be the sample space for the experiment when order of picking marbles does matter.
For this, First give numbers to the balls in bag i.e.,
First Red ball in the bag = R1
Second Red ball in the bag = R2
First Blue ball in the bag = B1
Second Blue ball in the bag = B2
Yellow ball in the bag = Y
Now the cases for sample spaces when two marbles are selected will be :
{R1 R2, R1 B1, R1 B2, R1 Y, R2 R1, R2 B1, R2 B2, R2 Y, B1 R1, B1 R2, B1 B2, B1 Y, B2 R1, B2 B1, B2 R2, B2 Y, Y R1, Y R2, Y B1, Y B2}.
A group of 22 7th grade girls is to be divided into a varsity team and a junior varsity team of 11 each. How many different divisions are possible?
Answer:
705,432 ways
Step-by-step explanation:
Since no girl will be left out once both teams are selected when selecting the varsity team, the junior varsity team is automatically composed by the players not selected, the number of ways to select both teams is:
[tex]n = \frac{22!}{(22-11)!11!} \\n=705,432[/tex]
There are 705,432 ways to divide the girls into a varsity team and a junior varsity team.
A researcher is studying psychological factors in academic achievement among teenage girls. One variable he is particularly interested in is competitiveness. What information does a measure of variability for the variable competitiveness convey?
a.Do all teenage girls have the same amount of competitiveness?
b.How spread out are the values for competitiveness amoung teenage girls?
c.What is the central tendency for the variable competitiveness among teenage girls?
d.What is the most common value for the variable competitiveness among teenage girls?
Answer:
The information a measure of variability for the variable competitiveness conveys is
The first option is correct
a.) Do all teenage girls have the same amount of competitiveness?
The second option is correct
b.) How spread out are the values for competitiveness among teenage girls?
Step-by-step explanation:
The first option is correct
a.) Do all teenage girls have the same amount of competitiveness?
The second option is correct
b.) How spread out are the values for competitiveness among teenage girls?
The third option is NOT correct. The given problem is a measure of dispersion not central tendency.
c.) What is the central tendency for the variable competitiveness among teenage girls?
The fourth option is also NOT correct. The problem given does not talk about a specific value of the competitiveness variable but rather it talks about the variability of the competitiveness variable
d.) What is the most common value for the variable competitiveness among teenage girls?
You are given the probability that an event will happen. Find the probability that the event will not happen.
1. P(E) = 0.7
2. P(E) = 0.36
3. P(E) = 1/4
4. P(E) = 2/3
Answer:
1) 0.3
2) 0.64
3) 0.75
4) 0.33
Step-by-step explanation:
We are given the following probabilities. We have to probability of that event not happening.
That is we have to find the complement of the event,
Complement of event:
The complement of event E is represented as E'.[tex]P(E') = 1 - P(E)[/tex]1. P(E) = 0.7
[tex]P(E') = 1 - P(E) = 1 - 0.7 =0.3[/tex]
2. P(E) = 0.36
[tex]P(E') = 1 - P(E) = 1 - 0.36 = 0.64[/tex]
3. P(E) = 1/4
[tex]P(E') = 1 = P(E) = 1 -\dfrac{1}{4} = \dfrac{3}{4} = 0.75[/tex]
4. P(E) = 2/3
[tex]P(E') = 1 = P(E) = 1 -\dfrac{2}{3} = \dfrac{1}{3} = 0.33[/tex]
For two independent events, A and B, P(A)equals . 3 andP(B)equals . 2 . a. Find P(Aintersect B). b. Find P(A|B). c. Find P(Aunion B). a. P(Aintersect B)equalsnothing b.P(A|B)equals nothing c. P(Aunion B)equalsnothing. Any expert yet
Answer:
a) 0.06
b) 0.3
c) 0.44
Step-by-step explanation:
We are given the following in the question:
A and B are two independent events.
P(A) = 0.3
P(B) = 0.2
a) P(A intersect B)
[tex]P(A\cap B) = P(A)\times P(B) = 0.3\times 0.2 = 0.06[/tex]
b) P(A|B)
[tex]P(A|B) = \dfrac{P(A\cap B)}{P(B)} = \dfrac{0.06}{0.2} = 0.3[/tex]
c) P(A union B)
[tex]P(A\cup B) = P(A) + P(B) - P(A\cap B)\\P(A\cup B) = 0.3 + 0.2 - 0.06 = 0.44[/tex]
A scientist is working with 1.3m of gold wire. How long is the wire in millimeters
Answer:
1300 mm
Step-by-step explanation:
You want to convert metres to millimetres, so you multiply the metres by a conversion factor:
1.3 m × conversion factor = x mm
1 m = 1000 mm.
So, the conversion factor is either (1 m/1000 mm) or (1000 mm/1 m).
We choose the latter, because it has the desired units on top.
The calculation becomes
[tex]\text{Length} = \text{1.3 m} \times \dfrac{\text{1000 mm}}{\text{1 m}} = \textbf{1300 mm}[/tex]
Average Earnings of Workers The average earnings of year-round full-time workers 25–34 years old with a bachelor’s degree or higher were $58,500 in 2003. If the standard deviation is $11,200, what can you say about the percentage of these workers who earn?
a. Between $47.300 and $69,700?
b. More than $80.900?
c. How likely is it that someone earns more than $100,000?
Answer:
a. 68% of the workers will earn between $47300 and $69700.
b. 2.5% of workers will earn above $89000
c. Approximately 0
Step-by-step explanation:
The standard normal distribution curve in the attached graph is used to solve this question.
a. The value $47300 is a standard deviation below the mean i.e. 58500-11200=47300. While $69700 is a standard deviation above the mean. I.e. 58500+12000=69700.
Between the first deviation below and above the mean, you have 34%+34%=68% of the salary earners within this range. So we have 68%of staffs earning within this range
b. The second standard deviation above the mean is $80900. i.e. 58500+11200+11200=$80900
We have 50%+13.5%+2.5%= 97.5% earning below $80900. Therefore, 100-97.5= 2.5% of the workers earn above this amount.
c. From the Standard Deviation Rule, the probability is only about (1 -0 .997) / 2 = 0.0015 that a normal value would be more than 3 standard deviations away from its mean in one direction or the other. The probability is only 0.0002 that a normal variable would be more than 3.5 standard deviations above its mean. Any more standard deviations than that, and we generally say the probability is approximately zero.
To answer the question, we use z-scores and a z-table to find the percentages of workers who earn within certain ranges or above certain amounts.
Explanation:To answer this question, we can use the concept of the standard normal distribution. First, we convert the given earnings into z-scores by subtracting the mean and dividing by the standard deviation. With these z-scores, we can then use a z-table to find the percentage of workers who earn within a certain range or above a certain amount.
a. To find the percentage of workers who earn between $47,300 and $69,700, we need to convert these values into z-scores and find the area between these two z-scores on the z-table.
b. To find the percentage of workers who earn more than $80,900, we need to convert this value into a z-score and find the area to the right of this z-score on the z-table.
c. To determine how likely it is that someone earns more than $100,000, we need to convert this value into a z-score and find the area to the right of this z-score on the z-table.
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A manufacturing company has 5 identical machines that procuce nails. The probability that a machine will break down on any given day is 0.1. Define a random variable x to be the number of machines that will break down in a day.
a. What is the appropriate probability distribution for x? Explain how x satisfies the properties of the distribution.
b. Compute the probability that 4 machines will break down.
c. Compute the probability that at least 4 machines will break down.
d. What is expected number of machines that will break down in a day?
e. What is the variance of the number of machines that will break down in a day?
Answer:
a) Binomial probability distribution. Only two outcomes possible for each machine, with independent probabilities.
b) [tex]P(X = 4) = 0.00045[/tex]
c) [tex]P(X \geq 4) = 0.00046[/tex]
d) [tex]E(X) = 0.5[/tex]
e) [tex]V(X) = 0.45[/tex]
Step-by-step explanation:
For each machine, there is only two possibilities. On a given day, either they will break down, or they will not. The probabilities for each machine breaking down are independent. So we use the binomial probability distribution to solve this problem.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
The expected value of the binomial distribution is:
[tex]E(X) = np[/tex]
The variance of the binomial distribution is:
[tex]V(X) = np(1-p)[/tex]
In this problem we have that:
[tex]n = 5, p = 0.1[/tex]
a. What is the appropriate probability distribution for x? Explain how x satisfies the properties of the distribution.
Binomial probability distribution. Only two outcomes possible for each machine, with independent probabilities.
b. Compute the probability that 4 machines will break down.
This is [tex]P(X = 4)[/tex].
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 4) = C_{5,4}.(0.1)^{4}.(0.9)^{1} = 0.00045[/tex]
c. Compute the probability that at least 4 machines will break down.
This is
[tex]P(X \geq 4) = P(X = 4) + P(X = 5)[/tex]
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 4) = C_{5,4}.(0.1)^{4}.(0.9)^{1} = 0.00045[/tex]
[tex]P(X = 5) = C_{5,5}.(0.1)^{5}.(0.9)^{0} = 0.00001[/tex]
[tex]P(X \geq 4) = P(X = 4) + P(X = 5) = 0.00045 + 0.00001 = 0.00046[/tex]
d. What is expected number of machines that will break down in a day?
[tex]E(X) = np = 5*0.1 = 0.5[/tex]
e. What is the variance of the number of machines that will break down in a day?
[tex]V(X) = np(1-p) = 5*0.1*0.9 = 0.45[/tex]
The random variable x follows a binomial distribution with n=5 and p=0.1. The probability of exactly 4 machines breaking down is approximately 0.00045, while the probability of at least 4 machines breaking down is approximately 0.00046. The expected number of machines that will break down is 0.5 and the variance is 0.45.
Explanation:The appropriate probability distribution for x is the binomial distribution. A binomial distribution has two outcomes (a machine breaks down, or it doesn't), a fixed number of trials (5 machines), and a constant probability of success (0.1, a machine breaks down). x satisfies all these properties.
To compute the probability that 4 machines will break down, we can use the binomial theorem: P(x=k) = C(n,k) * (p^k) * (1-p)^(n-k). Here, n=5, k=4, p=0.1. The calculation gives us approximately 0.00045 as the probability that exactly 4 machines will break down.
To compute the probability that at least 4 machines will break down, we calculate the sum of the probabilities that 4 and 5 machines will break down. It's approximately 0.00046.
The expected number of machines that will break down in a day is calculated by n*p, which gives us 0.5 machines.
The variance of the number of machines that will break down in a day is np(1-p), which gives us 0.45.
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If Mike does his mathematics homework today, the probability that he will do it tomorrow is 0.8. The probability that he will do his homework today is 7.0. What are the odds that he will do it both today and tomorrow?a. 4:1b. 8:7c. 3:2d. 14:11
Answer:
d. 14:11
Step-by-step explanation:
There is a 7 in 10 chance that Mike does his homework today and a 8 in 10 chance he will do it tomorrow, the probability that he will do it both today and tomorrow is:
[tex]P = \frac{7}{10}* \frac{8}{10}\\P=\frac{56}{100}=0.56[/tex]
The odds are the probability that an event occurs over the probability that it does not occur:
[tex]Odds = \frac{0.56}{1-0.56}=\frac{56}{44}=\frac{14}{11}[/tex]
The odds that he will do it both today and tomorrow are 14:11.
The odds that he will do it both today and tomorrow is 14:11.
What are the odds that he will do it both today and tomorrow?
Probability that he would do the assignement today and tomorrow = probability he would do the assignment today x probability he would do the assignment tomorrow
0.7 x 0.8 = 0.56
Odds he would do the assignment today and tomorrow = 0.56/ (1 - 0.56) = 0.56 / 0.44
= 14 : 11
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Suppose we are interested in bidding on a piece of land and we know one other bidder is interested. The seller announced that the highest bid in excess of $10,400 will be accepted. Assume that the competitor's bid x is a random variable that is uniformly distributed between $10,400 and $14,600.a. Suppose you bid $12,000. What is the probability that your bid will be accepted (to 2 decimals)?b. Suppose you bid $14,000. What is the probability that your bid will be accepted (to 2 decimals)?c. What amount should you bid to maximize the probability that you get the property (in dollars)?d. Suppose that you know someone is willing to pay you $16,000 for the property. You are considering bidding the amount shown in part (c) but a friend suggests you bid $13,200. If your objective is to maximize the expected profit, what is your bid? (Options: 1. Stay with the bid in part (c) or 2. Bid $13,200 to maximize profit)What is the expected profit for this bid (in dollars)?
Final answer:
a. The probability that your bid will be accepted is 60%. b. The probability that your bid will be accepted is 10%. c. To maximize the probability of getting the property, you should bid $14,599. d. To maximize expected profit, bid $14,599 with an expected profit of $700.50.
Explanation:
a. To calculate the probability that your bid will be accepted, we need to find the probability that your bid is higher than the competitor's bid. Since the competitor's bid, x, is uniformly distributed between $10,400 and $14,600, the probability that the competitor's bid is less than $12,000 is given by:
P(x < 12,000) = (12,000 - 10,400) / (14,600 - 10,400) = 0.4
Therefore, the probability that your bid will be accepted is 1 - P(x < 12,000) = 1 - 0.4 = 0.6, or 60%.
b. Using the same method, the probability that your bid will be accepted when you bid $14,000 is:
P(x < 14,000) = (14,000 - 10,400) / (14,600 - 10,400) = 0.9
Therefore, the probability that your bid will be accepted is 1 - P(x < 14,000) = 1 - 0.9 = 0.1, or 10%.
c. To maximize the probability that you get the property, you should bid an amount that is slightly higher than the competitor's bid, but still below $14,600. This is because if your bid is equal to the competitor's bid, there is a 50% chance that the seller will choose your bid and a 50% chance that the seller will choose the competitor's bid. Therefore, to maximize your chances, you should bid $14,599.
d. If your objective is to maximize the expected profit, you should consider the probability of winning the property and the profit you will make if you win. Since you know someone is willing to pay you $16,000 for the property, the expected profit can be calculated as:
Expected Profit = Probability of Winning × (Selling Price - Bidding Amount)
According to part (c), if you bid $14,599, the probability of winning is 0.5. Therefore, the expected profit is:
Expected Profit = 0.5 × (16,000 - 14,599) = $700.50
a. Probability of bid acceptance when bidding $12,000 is approximately 0.38.
b. Probability of bid acceptance when bidding $14,000 is approximately 0.86.
c. To maximize chances, bid $12,500.
d. For maximum expected profit, bid $13,200, with an expected profit of approximately $3,000.
Let's break down the problem step by step:
a. Probability of bid acceptance when bidding $12,000:
Given that the competitor's bid ( x ) is uniformly distributed between $10,400 and $14,600, we need to find the probability that our bid is higher than $10,400 but less than $14,600.
[tex]\[ P(10400 < x < 12000) = \frac{12000 - 10400}{14600 - 10400} = \frac{1600}{4200} \][/tex]
b. Probability of bid acceptance when bidding $14,000:
[tex]\[ P(10400 < x < 14000) = \frac{14000 - 10400}{14600 - 10400} = \frac{3600}{4200} \][/tex]
c. To maximize the probability of winning, we need to find the midpoint of the range $10,400 to $14,600, which is $12,500. So, we should bid $12,500.
d. Expected profit when bidding $12,500:
If someone is willing to pay $16,000 for the property, and we win the bid, our profit would be $16,000 - $12,500 = $3,500. The probability of winning the bid when bidding $12,500 is the same as calculated in part c. So, the expected profit would be:
[tex]\[ E(Profit) = (Probability \ of \ winning) \times (Profit \ if \ won) \][/tex]
[tex]\[ E(Profit) = \frac{3600}{4200} \times 3500 \][/tex]
Now, let's calculate:
a. [tex]\[ P(10400 < x < 12000) = \frac{1600}{4200} \approx 0.38 \][/tex]
b.[tex]\[ P(10400 < x < 14000) = \frac{3600}{4200} \approx 0.86 \][/tex]
c. Midpoint: $12,500
d. [tex]\[ E(Profit) = \frac{3600}{4200} \times 3500 \approx 3000 \][/tex]
So, to maximize expected profit, the bid should be $13,200.
An airline charges the following baggage fees: $25 for the first bag and $35 for the second. Suppose 51% of passengers have no checked luggage, 32% have one piece of checked luggage and 17% have two pieces. We suppose a negligible portion of people check more than two bags. The average baggage-related revenue per passenger is: _____.
Answer:
The average baggage-related revenue per passenger is $18.20
Step-by-step explanation:
$25 for the first bag
$35 for the second bag
Total passenger = 100
51 passenger have no checked baggage
32 passenger have one checked baggage. Therefore the airlines charges for the 32 passenger will be: [tex]25 * 32 = 800[/tex].
17 passenger have two checked baggage. Therefore the airline charges for the 17 passenger will be: [tex](25 *17) + (35*17) = 425+595=1020[/tex]
Average baggage related revenue per passenger is: Total Revenue / passenger
Total Revenue = 1020 + 800 = $1820
Average = 1820/100 = $18.20
Suppose you invest $2,500 in a fund earning 10% simple interest annually. After two years you have the option of moving your money to an account that pays compound interest at an annual effective rate of 7%. Should you move your money to the compound interest account (a) if you wish to liquidate in five more years?(b) if you are confident your money will stay on deposit for a total of ten years?
Answer:
account after 2 years of simple interest at 10%: (2,500 * 0.10 * 2) + 2500 = 3,000
Note that simple interest only pays interest on the original balance, NOT on the accrued (paid) interest....
a) 5 more years at 10% simple: (2500 * 0.10 * 5) + 3,000 = $4,250
or
5 years compound interest on $3k: 3,000(1.07^5) = $4,207.66
b) TOTAL of 10 years
simple interest: (2500 * 0.10 * 10) + 2500 = 5,000
compound interest: only 8 years remain of the total 10 year time horizon
3000(1.07^8) = $5,154.56
Step-by-step explanation:
After the initial 2 years with simple interest, moving the money to the account with compound interest yields a higher amount whether you liquidate in the next 5 years or keep it for a total of 10 more years.
Explanation:First, let's calculate the amount you will have after 2 years with a simple interest of 10%. Using the formula for simple interest, I = PRT, where P is the principal amount ($2,500), R is the rate of interest (10% as a decimal, 0.10), and T is the time in years (2): I = $2,500 * 0.10 * 2 = $500. Therefore, your total amount after 2 years would be $2,500 + $500 = $3,000.
To decide whether you should move your money, we need to calculate the final amount after the next 5 years and 10 years using compound interest formula, A = P(1 + r/n)^(nt), where P is the principal amount ($3,000), r is the annual interest rate (7% as a decimal, 0.07), n is the number of times interest applied per time period (1, for annual compounding), and t is the time the money is invested for.
(a) For 5 more years: A = $3,000 * (1 + 0.07/1)^(1*5) = $4,209.24.
(b) For a total of 10 more years: A = $3,000 * (1 + 0.07/1)^(1*10) = $5,922.58.
Therefore, If you intend to liquidate in five more years or you're confident your money will stay on deposit for a total of ten more years after the initial 2 years of simple interest, moving the money to the compound interest account is a good move as it results in a higher amount in both scenarios.
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A box contains three coins which have the same look. However, two of them are fair and theother one is biased withP(H) = 0.3. A coin is randomly selected from the box and tossed 10 times.(a)[15 points] What is the probability of observing exactly 3 heads?
Answer:
0.1673 (16.73%)
Step-by-step explanation:
The probability that a fair coin is chosen is 2/3 . if the fair coin is chosen the probability of getting 3 heads is determined by binomial distribution:
P(3 heads in 10 flips )=B(n=10,p=0.5,X=3) =0.1171
But if a coin that is not fair is chosen , then the probability of getting 3 heads also follows a binomial distribution but with p=0.3
P(3 heads)=B(n=10,p=0.3,X=3)=0.2668
Finally the probability is
P= 2/3*0.1171 + 1/3* 0.2678 = 0.1673 (16.73%)
In the 2012 National Football League (NFL) season, the first three weeks’ games were played with replacement referees because of a labor dispute between the NFL and its regular referees. Many fans and players were concerned with the quality of the replacement referees’ performance. We could examine whether data might reveal any differences between the three weeks’ games played with replacement referees and the next three weeks’ games that were played with regular referees. For example, did games generally take less or more time to play with replacement referees than with regular referees? The pair of dotplots below display data about the duration of games (in minutes), separated by the type of referees officiating the game.
Answer: for replacement total games = 47 more than 3.5 hours = 8 required proportion = 8/47 = 0.170212 for regular.
Step-by-step explanation:
1. What proportion of the 47 games officiated by replacement referees lasted for at least 3.5 hours (210 minutes)? What proportion of the 42 games officiated by regular referees lasted for this long?
2. What proportion of the 47 games officiated by replacement referees lasted for less than 3 hours (180 minutes)? What proportion of the 42 games officiated by regular referees lasted for this long?
3. Would you say that either type of referee tended to have longer games than the other on average, and if so, which type of referee tended to have longer games and by about how much on average?
i. Regular Referees have longer game times with games about 185 minutes on average.
ii. The game lengths for both referees seem to be the same.
iii. Replacement Referees have longer game times with games about 195 minutes on average.
iv. It is too hard to tell from the graph which type of referee has longer games.
4. Would you say that either type of referee tended to have more variability in game durations? If so, which type of referee tended to have more variability?
i. The two types of referees had the same amount of variability in the game lengths.
ii. There is no way to tell which group of referees had more variability in the game lengths.
iii. The regular referees tended to have more variability in the game lengths.
iv. The replacement referees tended to have more variability in the game lengths.
For replacement total games = 47 more than 3.5 hours = 8 required proportion = 8/47 = 0.170212 for regular.