A large disaster cleaning company estimates that 30 percent of the jobs it bids on are finished within the bid time. Looking at a random sample of 8 jobs that it has contracted, calculate the mean number of jobs completed within the bid time.

Answers

Answer 1

Answer: 2.4

Step-by-step explanation:

Given : A large disaster cleaning company estimates that 30 percent of the jobs it bids on are finished within the bid time.

i..e The proportion of  the jobs it bids on are finished within the bid time: p = 30%= 0.30

Sample size of jobs that it has contracted : n= 8

Then ,  the mean number of jobs completed within the bid time : [tex]\mu=np[/tex]

[tex]= 8\times0.30=2.4[/tex]

Hence, the mean number of jobs completed within the bid time is 2.4 .


Related Questions

Name the quadrant in which the angle below is located.
sine = 4 and cose is positive.

Answers

Answer:

first quadrant

Step-by-step explanation:

To know this we have to take into account that for the breast we have to look at the y-axis and in the cosine we will look at the x-axis

 We have the positive and the negative part of the x-axis, now we notice that it says that the cosine is positive, then the quadrant will be with the positive x,  these quadrants can be the first or the fourth.

Now if we look at sine = 4 is positive, this means that the axis y will also be positive,  this means that it will be between the first and second quadrant.

Now if we look to meet the conditions of the sine and cosine, the angle has to be found in the first quadrant

Quota sampling is most commonly used in a. descriptive research. b. collecting primary data. c. surveys. d. population research. e. exploratory studies.

Answers

Final answer:

Quota sampling is most commonly used in surveys. It is a non-probability sampling technique where researchers select individuals who meet certain criteria to be included in the sample.

Explanation:

Quota sampling is most commonly used in surveys. It is a non-probability sampling technique where researchers select individuals who meet certain criteria to be included in the sample.

In quota sampling, the researcher sets quotas or targets for each subgroup they want to include in the sample based on certain characteristics. For example, if the researcher wants equal representation of males and females in the sample, they would set quotas for each gender and continue selecting individuals until the quotas are met.

Quota sampling is often used when it is not possible or practical to obtain a random sample, but the researcher still wants to ensure representation of different subgroups within the sample.

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A history class is comprised of 7 female and 10 male students. If the instructor of the class randomly chooses 7 students from the class for an oral exam, what is the probability that 5 female students and 2 male students will be selected? Round your answer to 3 decimal places.

Answers

Answer:

The probability of selecting 5 female and 2 male students is 0.052.

Step-by-step explanation:

The class comprises of 7 female students and 10 male students.

Total number of students: 17.

Number of female students, 7.

Number of male students, 10.

The probability of an event E is:

[tex]P(E)=\frac{Favorable\ outcomes}{Total\ number\ of] outcomes}[/tex]

The number of ways to select 7 students from 17 is:

[tex]N ={17\choose 7}=\frac{17!}{7!(17-7)!}= 19448[/tex]

The number of ways to select 5 female students of 7 females is:

[tex]n(F) ={7\choose 5}=\frac{7!}{5!(7-5)!}= 21[/tex]

The number of ways to select 2 male students of 10 males is:

[tex]n(M) ={10\choose 2}=\frac{10!}{2!(10-2)!}= 45[/tex]

Compute the probability of selecting 5 female and 2 male students as follows:

P (5 F and 2 M) = [n (F) × n (M)] ÷ N

                         [tex]=\frac{21\times45}{19448} \\=0.05183\\\approx0.052[/tex]

Thus, the probability of selecting 5 female and 2 male students is 0.052.

Money Flow  The rate of a continuous money flow starts at $1000 and increases exponentially at 5% per year for 4 years. Find the present value and accumulated amount if interest earned is 3.5% compounded continuously.

Answers

Answer:

Present value =  $4,122.4

Accumulated amount = $4,742

Step-by-step explanation:

Data provided in the question:

Amount at the Start of money flow = $1,000

Increase in amount is exponentially at the rate of 5% per year

Time = 4 years

Interest rate = 3.5%  compounded continuously

Now,

Accumulated Value of the money flow = [tex]1000e^{0.05t}[/tex]

The present value of the money flow = [tex]\int\limits^4_0 {1000e^{0.05t}(e^{-0.035t})} \, dt[/tex]

= [tex]1000\int\limits^4_0 {e^{0.015t}} \, dt[/tex]

= [tex]1000\left [\frac{e^{0.015t}}{0.015} \right ]_0^4[/tex]

= [tex]1000\times\left [\frac{e^{0.015(4)}}{0.015} -\frac{e^{0.015(0)}}{0.015} \right][/tex]

= 1000 × [70.7891 - 66.6667]

= $4,122.4

Accumulated interest = [tex]e^{rt}\int\limits^4_0 {1000e^{0.05t}(e^{-0.035t}} \, dt[/tex]

= [tex]e^{0.035\times4}\times4,122.4[/tex]

= $4,742

The present value and interest accumulated would be as follows:

Present Value = $ 4,122.4

Interest Accumulated = $ 4742

Given that,

Principal at the beginning of money flow = $1,000

Exponential interest rate = 5% per year

Time Period = 4 years

So,

The accumulated money flow's worth = [tex]1000e^{0.05t}[/tex]

The current value of the money can be determined by [tex]\int\limits^4_0 1000e^{0.05t}(e^{-0.035t}) {} \, dt[/tex]

On solving, we get

The present value = $ 4,122.4

Interest Accumulated = $4,742

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A baseball enthusiast believes pitchers who strike out a lot of batters also walk a lot of batters. He reached this conclusion by going to the library and examining the records of all major league pitchers between 1990 and 1995. What type of study is his decision based on? A) B) C) An observational study based on a sample survey D) An experiment. Anecdotal evidence. An observational study based on available data.

Answers

Answer:

D) An observational study based on available data.

Step-by-step explanation:

This is an observational study based on available data.

If it had been on a sample, he would take a sample of a few pitchers, and not studied the statistics of all major league pitchers during those seasons.

It is not an anecdotal evidence, because an anecdotal evidence is something without study, just an impression.

It is not an experiment, because he just studies(observes, that is why it is an observational study) the data, he does not change anything about the pitchers.

So the correct answer is:

D) An observational study based on available data.

Final answer:

The baseball enthusiast's decision is based on an observational study based on available data.

Explanation:

The baseball enthusiast's decision is based on A) an observational study based on available data. In this case, the enthusiast examined the records of all major league pitchers between 1990 and 1995. This observational study involved collecting and analyzing data that was already available, without manipulating any variables or conducting an experiment.

gasoline wholesale distributor has bulk storage tanks holding a fixed supply. The tanks are filled every Monday. Of interest to the wholesaler is the proportion of this supply that is sold during the week. Over many weeks, this proportion has been observed to be modeled fairly well by a beta distribution with alpha = 4 and beta = 2. Find the probability that at least 90% of the stock will be sold in a given week? a. 0.07 b. 0.05 c. 0.09 d. 0.06 e. 0.08

Answers

Answer:

e. 0.08

Step-by-step explanation:

In the question above, a certain quantity of goods was supplied while a specific quantity of goods was sold per week. In a given week, if the number of proportion sold is X, therefore:

f(x) = {Γ(4+2)/Γ(4)Γ(2) x^3 (1-x), 0≤x≤1 ; 0, elsewhere

and

P(X greater than 0.9) =  [tex]\int\limits^1_ {0.9} \, 20(x^{3} - x^{4}) dx[/tex] = 20*{(y^4/4)[1,0.9] - (y^5/5)[1,0.9]} = 20*{(0.25 - 0.164) - (0.20 - 0.118)}  = 20*{0.086 - 0.0819} = 20*0.0041 = 0.082

Therefore the probability of the proportion sold is approximately 0.082

The probability that at least 90% of the stock will be sold in a given week is approximately 0.05. The correct answer option is b. 0.05

Here's how to calculate it:

1. Given the beta distribution with parameters alpha = 4 and beta = 2, we want to find [tex]\( P(X > 0.9) \)[/tex], where X represents the proportion of stock sold in a week.

2. Since [tex]\( P(X > 0.9) = 1 - P(X \leq 0.9) \)[/tex], we need to find the cumulative distribution function (CDF) of the beta distribution and then subtract it from 1.

3. Using the incomplete beta function formula [tex]\( I_{x}(\alpha, \beta) \)[/tex], we have:

[tex]\[ P(X > 0.9) = 1 - I_{0.9}(4, 2) \][/tex]

4. Calculating [tex]\( I_{0.9}(4, 2) \)[/tex] using software or a calculator gives approximately 0.95.

5. Subtracting this from 1:

[tex]\[ P(X > 0.9) = 1 - 0.95 = 0.05 \][/tex]

So, the correct answer is b. 0.05.

Consider an airfoil in a wind tunnel (i.e., a wing that spans the entire test section). Prove that the lift per unit span can be obtained from the pressure distributions on the top and bottom walls of the wind tunnel (i.e., from the pressure distributions on the walls above and below the airfoil).

Answers

Answer:

The solution proved are in the attached file below. Also the explanation is in the attached file

Step-by-step explanation:

A recent survey found that 71% of senior adults wear glasses for driving. In a group of 20 senior adults, how like that no more than 10 wear glasses for driving? Group of answer choices 95.2% 4.8% 3.1% 1.7%

Answers

Answer:

[tex] P(X\leq 10) = 1- 0.961525= 0.0385[/tex]  

The nearest answer for this case would be 3.1%

Step-by-step explanation:

Previous concepts

The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".

Solution to the problem

Let X the random variable of interest, on this case we now that:

[tex]X \sim Binom(n=20, p=0.71)[/tex]

The probability mass function for the Binomial distribution is given as:

[tex]P(X)=(nCx)(p)^x (1-p)^{n-x}[/tex]

Where (nCx) means combinatory and it's given by this formula:

[tex]nCx=\frac{n!}{(n-x)! x!}[/tex]

For this case we can begin finding the probability P(X>10). If we find the individual probabilities we got:

[tex]P(X=11)=(20C11)(0.71)^{11} (1-0.71)^{20-11}=0.0563[/tex]

[tex]P(X=12)=(20C12)(0.71)^{12} (1-0.71)^{20-12}=0.1034[/tex]

[tex]P(X=13)=(20C13)(0.71)^{13} (1-0.71)^{20-13}=0.1558[/tex]

[tex]P(X=14)=(20C14)(0.71)^{14} (1-0.71)^{20-14}=0.1907[/tex]

[tex]P(X=15)=(20C15)(0.71)^{15} (1-0.71)^{20-15}=0.1867[/tex]

[tex]P(X=16)=(20C16)(0.71)^{16} (1-0.71)^{20-16}=0.1429[/tex]

[tex]P(X=17)=(20C17)(0.71)^{17} (1-0.71)^{20-17}=0.082[/tex]

[tex]P(X=18)=(20C18)(0.71)^{18} (1-0.71)^{20-18}=0.036[/tex]

[tex]P(X=19)=(20C19)(0.71)^{19} (1-0.71)^{20-19}=0.0087[/tex]

[tex]P(X=20)=(20C20)(0.71)^{20} (1-0.71)^{20-20}=0.00106[/tex]

And if we add the values we got:

[tex] P(X>10)= P(X=11) +.... +P(X=20) = 0.961525[/tex]

And if we use the complement rule the probability that "no more than 10 wear glasses for driving" we can do this:

[tex] P(X\leq 10) = 1- 0.961525= 0.0385[/tex]  

The nearest answer for this case would be 3.1%

We select two distinct numbers (a, b) in the range 1 to 99 (inclusive). How many ways can we pick a and b such that their sum is even and a is a multiple of 9?

Answers

Answer:

The possible number of ways to select distinct (a, b) such that (a + b) is even is 534.

Step-by-step explanation:

The range 1 - 99 has 99 numbers, since 1 and 99 are inclusive.

Of these 50 numbers are odd and 49 are even.

The two distinct numbers a and b must have an even sum and a should be a multiple of 9.

The sum of two numbers is even only when both are odd or both are even.

The possible values that a can assume are,

a = {9, 18, 27, 36, 45, 54, 63, 72, 81, 90 and 99}

Thus, a can assume 6 odd values and 5 even values.

If a = odd number, then b can be any of the 49 out of 50 odd numbers.

Total number of ways to select a and b such that both are odd and their sum is even is:

[tex]n(Odd\ a\ and\ b)=n(Odd\ value\ of\ a)\times n(Odd\ value\ of\ b)=6\times49=294[/tex]

If a = even number, then b can be any of the 48 out of 50 even numbers.

Total number of ways to select a and b such that both are even and their sum is even is

[tex]n(Even\ a\ and\ b)=n(E\ value\ of\ a)\times n(Even\ value\ of\ b)=5\times48=240[/tex]

Total number of ways to select distinct (a, b) such that (a + b) is even is =

[tex]=n(Odd\ a\ and\ b)+n(Even\ a\ and\ b)=294+240=534[/tex]

Thus, the possible number of ways to select distinct (a, b) such that (a + b) is even is 534.

A switchboard display in the store allows a customer to hook together any selection of components (consisting of one of each type). Use the product rules to answer the following questions: a. In how many ways can one component of each type be selected

Answers

Answer:  

120 ways

Step-by-step explanation: If there are three different categories of components, that is, component A, comprising four types; component B comprising, five types and component C comprising, six types. Three types are to be selected, that is, one type from each category. The number of ways one component of each type be selected is:

Component A * Component B * Component C = 4 X 5 X 6 = 120

The Dow Jones Industrial Average has had a mean gain of 432 pear year with a standard deviation of 722. A random sample of 40 years is selected. What is the probability that the mean gain for the sample was between 250 and 500?

Answers

Answer:

66.98% probability that the mean gain for the sample was between 250 and 500.

Step-by-step explanation:

To solve this problem, it is important to know 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], a large sample size can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]\frac{\sigma}{\sqrt{n}}[/tex].

In this problem, we have that:

[tex]\mu = 432, \sigma = 722, n = 40, s = \frac{722}{\sqrt{40}} = 114.16[/tex]

What is the probability that the mean gain for the sample was between 250 and 500?

This is the pvalue of Z when X = 500 subtracted by the pvalue of Z when X = 250.

So

X = 500

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

By the Central Limit Theorem

[tex]Z = \frac{X - \mu}{s}[/tex]

[tex]Z = \frac{500 - 432}{114.16}[/tex]

[tex]Z = 0.6[/tex]

[tex]Z = 0.6[/tex] has a pvalue of 0.7257.

X = 250

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

By the Central Limit Theorem

[tex]Z = \frac{X - \mu}{s}[/tex]

[tex]Z = \frac{250 - 432}{114.16}[/tex]

[tex]Z = -1.59[/tex]

[tex]Z = -1.59[/tex] has a pvalue of 0.0559.

So there is a 0.7257 - 0.0559 = 0.6698 = 66.98% probability that the mean gain for the sample was between 250 and 500.

The probability that the mean gain for a sample of 40 years is between 250 and 500 is approximately 0.6698, or 66.98%.

To determine the probability that the mean gain for a random sample of 40 years of the Dow Jones Industrial Average is between 250 and 500, we will use the concept of the sampling distribution of the sample mean. The steps involved are:

State the given information:

  - Population mean [tex](\(\mu\))[/tex] = 432

  - Population standard deviation [tex](\(\sigma\))[/tex] = 722

  - Sample size n = 40

Find the standard error of the mean (SEM):

  The standard error of the mean is calculated as:

  [tex]\[ \text{SEM} = \frac{\sigma}{\sqrt{n}} = \frac{722}{\sqrt{40}} \approx 114.2 \][/tex]

Convert the sample means to z-scores:

  To find the probability that the sample mean [tex](\(\bar{x}\))[/tex] is between 250 and 500, we convert these values to z-scores using the formula:

  [tex]\[ z = \frac{\bar{x} - \mu}{\text{SEM}} \] For \(\bar{x} = 250\): \[ z = \frac{250 - 432}{114.2} \approx \frac{-182}{114.2} \approx -1.59 \] For \(\bar{x} = 500\):[/tex]

  [tex]\[ z = \frac{500 - 432}{114.2} \approx \frac{68}{114.2} \approx 0.60 \][/tex]

Find the probability corresponding to the z-scores:

  Using the standard normal distribution table or a calculator, we find the probabilities corresponding to these z-scores.

   [tex]\(z = -1.59\), \(P(Z \leq -1.59) \approx 0.0559\) \\\(z = 0.60\), \(P(Z \leq 0.60) \approx 0.7257\)[/tex]

Calculate the probability that the mean gain is between 250 and 500:

  \[tex][ P(250 \leq \bar{x} \leq 500) = P(Z \leq 0.60) - P(Z \leq -1.59) \] \[[/tex]

 = 0.7257 - 0.0559 = 0.6698

Conclusion:

The probability that the mean gain for a sample of 40 years is between 250 and 500 is approximately 0.6698, or 66.98%.

A basketball player shoots a basketball with an initial velocity of 15 ft/sec. The ball is released from an initial height of 6.5 feet.

The function ℎ()=−162+0+h0 models the height, in feet, of an object after t seconds. v0 is the initial velocity of the object, and h0 is the initial height of the object.

Part 1: Write a function that models the height of the basketball. Use your function to answer Parts 2-4.

Part 2: How long does it take for the basketball to hit the ground? Round your answer to the nearest hundredth. Show all of your work. You're welcome to use this quadratic formula calculator, but please explain your answer.

Part 3: When does the basketball reach its maximum height? Round your answer to the nearest hundredth. Show all of your work and explain your answer.

Part 4: What is the maximum height of the basketball? Round your answer to the nearest hundredth. Show all of your work and explain your answer.

Answers

Answer:

Step-by-step explanation:

Let R be the region bounded by y=x^2, x=1, and y=0. use the shell method to find the volume of the solid generated when R is revolved about the line x= 2

Answers

Answer:

[tex]V = \frac{5\pi}{6}[/tex] or 2.62

Step-by-step explanation:

Since our region (on the left) is bounded by x = 1 and x = 0 (where [tex]y = x^2 = 0[/tex], if we take center at x = 2 then our radius will range from 1 to 2 (x=1 to x = 0). We can use the following integration to calculate the volume using shell method

[tex]V = \int\limits^2_1 {2\pi r h} \, dr[/tex]

where r = 2 - x so x = 2 - r and [tex]h = y = x^2 = (2-r)^2[/tex] for [tex]1 \leq r \leq 2[/tex]

[tex]V = \int\limits^2_1 {2\pi r(2-r)^2} \, dr[/tex]

[tex]V = \int\limits^2_1 {2\pi r(4 - 4r + r^2)} \, dr[/tex]

[tex]V = 2\pi \int\limits^2_1 {r^3 - 4r^2 +4r} \, dr[/tex]

[tex]V = 2\pi\left[\frac{r^4}{4} - \frac{4r^3}{3} + 2r^2\right]^2_1[/tex]

[tex]V = 2\pi\left[\left(\frac{2^4}{4} - \frac{4*2^3}{3} + 2*2^2\right) - \left(\frac{1^4}{4} - \frac{4*1^3}{3} + 2*1^2\right)\right][/tex]

[tex]V = 2\pi(4 - 32/3 +8 - 1/4 + 4/3 - 2)[/tex]

[tex]V = \pi(20 - 56/3 - 1/2)[/tex]

[tex]V = \pi\frac{120 - 112 - 3}{6}[/tex]

[tex]V = \frac{5\pi}{6}[/tex] or 2.62

Preston and Joel are both solving the equation 2x=14. Preston is not sure what to do because he does not know a power of 2 that equals 14. Joel uses his calculator to graph y=2x and y=14 and find the point of intersection. Will Joel's method work?

Answers

Answer:

  yes

Step-by-step explanation:

You can always separate an equation into two parts and see where those graphs intersect.

Joel's method works well.

_____

Additional comments

Preston should know that the invention of logarithms makes it easy to solve equations like this. x = log₂(14) = log(14)/log(2) ≈ 3.8073549.

As for Joel's method, I prefer to subtract the right side to get the equation ...

  2^x -14 = 0

Then graphing y = 2^x -14, I look for the x-intercept. Most graphing calculators make it easy to find x- and y-intercepts. Not all make it easy to find points of intersection between different curves.

Answer:

Yes, the graph intersects around (3.807,14), so 3.807 is a good estimate of the solution to 2^x=14.

Step-by-step explanation:

The branch of statistical studies called inferential statistics refers to drawing conclusions about sample data by analyzing the corresponding population. True or False

Answers

Answer: False

Step-by-step explanation:

In Inferential statistics the sample data is analysed rather than analysing the whole population, analysing the whole population may sometimes be impossible, like analysing the population of a whole country. Therefore, for inferential statistics, conclusions about the whole population are drawn by analyzing the corresponding sample data. The sample data are selected from the population and then analysed, the results can then be used to conclude on the whole population.

Determine whether the relation R defined below is reflexive, irreflexive, symmetric, asymmetric, antisymmetric, or transitive. For each property, either explain why R has that property or give an example showing why it does not.

a) Let A = {1, 2, 3, 4} and let R = { (2, 3) }
b) Let A = {1, 2, 3, 4} and let R = { (1, 1), (1, 2), (1, 3), (2, 1), (2, 2), (2, 4), (3, 1), (3, 3), (4, 1), (4, 4) }.

Answers

Answer:

See below

Step-by-step explanation:

Remember some definitions about binary relations. If R⊆S×S then

R is reflexive if (a,a)∈R for all a∈SR is irreflexive if (a,a)∉R for all a∈SR is symmetric if (a,b)∈R implies (b,a)∈R for all a,b∈SR is asymmetric if (a,b)∈R implies (b,a)∉R for all a,b∈SR is antisymmetric if (a,b)∈R and (b,a)∈R imply that a=b, for all a,b∈SR is transitive if (a,b)∈R and (b,c)∈R imply (a,c)∈R for all a,b,c∈S

a) R is not reflexive since (1,1)∉R.

R is irreflexive, since (a,a)∉R for all a=1,2,3,4

R is asymmetric: (2,3)∈R and (3,2)∉R (thus R is not symmetric).

R is antisymmetric, there are no cases to check. R is transitive, there are no cases to check.

b) R is reflexive, checking case by case, (a,a)∈R for all a=1,2,3,4. Hence R is not irreflexive.

R is not asymmetric: (1,2)∈R but (2,1)∈R. R is not symmetric, since (4,1)∈R but (1,4)∉R

R is not antisymmetric: (1,2)∈R and (2,1)∈R but 1≠2.

R is not transitive: (1,2)∈R and (2,4)∈R but (1,4)∉R.

Approximately 10% of all people are left-handed. Consider a grouping of fifteen people. a.)State the random variable. b.)Write the probability distribution. c.)Draw a histogram. d.)Describe the shape of the histogram. e.)Find the mean. f.)Find the variance. g.)Find the standard deviation.

Answers

Answer:

a) left handed people

b) Binomial probability distribution with pdf

[tex]P(X=x)=15Cx0.1^{x} 0.9^{15-x}[/tex]

where x=0,1,2,...,15.

c) Histogram is attached

d) The shape of histogram depicts that distribution is rightly skewed.

e) 1.5

f) 1.35

g) 1.16

Step-by-step explanation:

a)

The random variable in the given scenario is " left handed people"

b)

The scenario represents the binomial probability distribution as the outcome is divided into one of two categories and experiment is repeated fixed number of times i.e. 15 and trails are independent. The pdf of binomial distribution is

[tex]P(X=x)=nCxp^{x} q^{n-x}[/tex]

Here n=15, p=0.1 and q=1-p=0.9.

So, the pdf would be

[tex]P(X=x)=15Cx0.1^{x} 0.9^{n-x}[/tex]

where x=0,1,2,...,15.

c)

Histogram is constructed by first computing probabilities on all x points i.e. x=0, x=1 , .... ,x=15 and then plotting all probabilities with respective x values. Histogram is in attached image.

d)

The tail of histogram is to the right side and thus the histogram depicts that given probability distribution is rightly skewed.

e)

The mean of binomial probability distribution is computed by multiplying number of trails and probability of success.

mean=np=15*0.1=1.5

f)

The variance of binomial probability distribution is computed by multiplying number of trails and probability of success and probability of failure.

variance=npq=15*0.1*0.9=1.35

g)

The standard deviation can be calculated by simply taking square root of variance

S.D=√npq=√1.35=1.16

The proportion of left-handed people follows a binomial distribution

The random variable is left-handed peopleThe probability distribution function is [tex]\mathbf{P(x) = ^nC_x 0.1^x 0.9^{n -x}}[/tex]The mean is 1.5The variance is 1.35The standard deviation is 1.16

The given parameters are:

[tex]\mathbf{n = 15}[/tex] -- the sample size

[tex]\mathbf{p = 10\%}[/tex] --- the proportion of left-handed people

(a) The random variable

The distribution is about left-handed people.

Hence, the random variable is left-handed people

(b) The probability distribution

If the proportion of left-handed people is 10%, then the proportion of right-handed people is 90%.

So, the probability distribution function is:

[tex]\mathbf{P(x) = ^nC_x p^x (1 - p)^{n -x}}[/tex]

This gives

[tex]\mathbf{P(x) = ^nC_x (10\%)^x (1 - 10\%)^{n -x}}[/tex]

[tex]\mathbf{P(x) = ^nC_x 0.1^x 0.9^{n -x}}[/tex]

Hence, the probability distribution function is [tex]\mathbf{P(x) = ^nC_x 0.1^x 0.9^{n -x}}[/tex]

(c) The histogram

To do this, we calculate P(x) for x = 0 to 15

[tex]\mathbf{P(0) = ^{15}C_0 \times 0.1^0 \times 0.9^{15 -0} = 0.206}[/tex]

[tex]\mathbf{P(1) = ^{15}C_1 \times 0.1^1 \times 0.9^{15 -1} = 0.343}[/tex]

.....

..

[tex]\mathbf{P(15) = ^{15}C_{15} \times 0.1^{15} \times 0.9^{15 -15} = 10^{-15}}[/tex]

See attachment for the histogram

(d) The mean

This is calculated as:

[tex]\mathbf{\bar x = np}[/tex]

So, we have:

[tex]\mathbf{\bar x = 15 \times 10\% }[/tex]

[tex]\mathbf{\bar x= 1.5}[/tex]

Hence, the mean is 1.5

(e) The variance

This is calculated as:

[tex]\mathbf{Var = np(1 - p)}[/tex]

So, we have:

[tex]\mathbf{Var = 15 \times 10\% \times (1 - 10\%)}[/tex]

[tex]\mathbf{Var = 1.35}[/tex]

Hence, the variance is 1.35

(f) The standard deviation

This is calculated as:

[tex]\mathbf{\sigma = \sqrt{Var}}[/tex]

So, we have:

[tex]\mathbf{\sigma = \sqrt{1.35}}[/tex]

[tex]\mathbf{\sigma =1.16}[/tex]

Hence, the standard deviation is 1.16

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Of the air conditioner repair shops listed in a particular phone book, 87% are competent. A competent repair shop can repair an air conditioner 85% of the time; an incompetent shop can repair an air conditioner 60% of the time. Suppose the air conditioner was repaired correctly.
A. Find the probability that it was repaired by a competent shop, given that it was repaired correctly.

Answers

Answer:

There is a 90.46% probability that it was repaired by a competent shop, given that it was repaired correctly.

Step-by-step explanation:

We have these following probabilities:

An 87% probability that an air conditioner repair shop is competent.

A 13% probability that an air conditioner repair shop is incompetent.

An 85% probability that an compotent shop can repair the air.

A 60% probability than an incompetent shop can repair the air.

This can be formulated as the following problem:

What is the probability of B happening, knowing that A has happened?

It can be calculated by the following formula

[tex]P = \frac{P(B).P(A/B)}{P(A)}[/tex]

Where P(B) is the probability of B happening, P(A/B) is the probability of A happening knowing that B happened and P(A) is the probability of A happening.

In this problem we have that:

Probability that it was repaired by a competent shop, given that it was repaired correctly.

P(B) is the probability that it was repaired by a competent shop. 87% of the shops are competent, so [tex]P(B) = 0.87[/tex]

P(A/B) is the probability that it was repaired correctly, given that it was repaired by a competent shop. There is an 85% probability that an compotent shop can repair the air. So [tex]P(A/B) = 0.85[/tex]

P(A) is the probability that an air was repaired correctly.

This is 85% of 87% and 60% of 13%. So

[tex]P(A) = 0.85*0.87 + 0.60*0.13 = 0.8175[/tex]

Finally

[tex]P = \frac{P(B).P(A/B)}{P(A)} = \frac{0.87*0.85}{0.8175} = 0.9046[/tex]

There is a 90.46% probability that it was repaired by a competent shop, given that it was repaired correctly.

Consider the demand curve Qd = 150 - 2P and the supply curve Qs = 50 + 3P. What is total expenditure at equilibrium? Make sure to round your answers to the nearest 100th percentage point. Also, do not write any symbol. For example, write 123.34 for $123.34. Let me know if you have questions. Good luck.

Answers

Answer:

20

Step-by-step explanation:

At equilibrium quantity demanded Qd equals quantity supply Qs

                              Qd = Qs      (At equilibrium)

     ⇒                   150 - 2P = 50 + 3P

solving for P in the equation,

                             3P + 2P = 150 - 50

                              5P = 100

                                [tex]P = \frac{100}{5}[/tex]

                                P = 20

 

A construction company needs to remove 2 1/6 tons of dirt from a construction site. They can remove 710 tons of dirt each hour. What is the total number of hours it will take to remove the dirt?

Answers

Answer:

13/4260 tons

Step-by-step explanation:

We have the rate at which they remove tons of dirt per hour. We also know that total that needs to be removed. We can determine the time by dividing  the amount of tons that need to be removed by the rate:

[tex]=(13/6)/\cdot{710}=13/4260[/tex]

will take 13/4260 hours to remove the dirt

A Gift for You makes floral arrangements and fruit baskets. The small business has a maximum of 40 hours per week available in the assembly department and a maximum of 10 hours per week in the packaging department. Each floral arrangement takes 20 minutes to assemble and 6 minutes to package. Each fruit basket takes 15 minutes to assemble and 2 minutes to package. The profit for each floral arrangement is $50 and the profit for each fruit basket is $35. The company wants to maximize their profit.a. Set up the linear programming problem by writing the objective function as well as the system of constraints. b. How many floral arrangements and fruit baskets must be sold to maximize profit? c. What is the maximum profit? Let x the number of floral arrangements and y the number of fruit baskets.Give the objective function a. Max P= 50x+ 35y b. Max P= 20x + 6y c. Min P= 15x+2yd. Max P= 35x +20ye. Min P= 35x+20yGive a constrainta. 20x+ 6y <=40b. 20x+15y<=40c. 6x+2y<=10d. 20x+ 15y<=24,00e. 6x+2y>=600How many of each should they sell to maximize their profit?a. 84 Floral Arrangements and 48 Fruit Baskets b. 0 Floral Arrangements and 160 Fruit Baskets c. 0 Floral Arrangements and 300 Fruit Baskets d. 100 Floral Arrangements and O Fruit Baskets e. 48 Floral Arrangements and 84 Fruit Baskets

Answers

Answer:

z(max)  =  5000

x   =  100

y   =  0

Step-by-step explanation:

Let call

x  floral arrangements  and

y  fruit baskets

Then Objective function is according to profits in each gift

z   =   50*x    +    35*y

Constraints:

1.- Hours available in Assembly department  40  in minutes   is  2400 minutes

20*x  +  15*y  ≤ 2400

2.- Hours available in packaging department 10 in minutes  is  600

6*x  + 2*y  ≤  600

3.- x    and    y must be    x ≥ 0    y  ≥ 0

Then the system is:

z      - 50*x       -   50*y                       =  0        To maximize subject to:

         20*x       +  15*y                        ≤  2400

           6*x        +   2*y                        ≤  600

x ≥ 0    y ≥ 0

Simplex Method:

z          x         y       s₁       s₂         Cte

1         -50     -35     0        0    =     0

0         20       15      1        0    =  2400

0           6         2      0        1    =  600

First iteration: 6 is a pivot   we dvede R3  by 6

z          x         y       s₁       s₂         Cte

1          0        15      0        50/6 =  5000

0         0      -50/6  -1        20/6 = -400                                                                

0         20       15      1        0    =  2400

0          1          2/6     0       1/6   =  100

We have done no negative number in the objective function we stop iteration and

z(max)  =  5000

x   =  100

y   =  0

                                         to add to R1  50*R3 [ 0  50  100/6  0  50/6  5000

                                         to add to R2 20*R3 [ 0   20  40/6   0  20/6  2000

Positive-sequence components consist of three phasors with _____ magnitudes and _____ phase displacement in positive sequence; negativesequence components consist of three phasors with _____ magnitudes and _____ phase displacement in negative sequence; and zero-sequence components consist of three phasors with _____ magnitudes and _____ phase displacement.

Answers

Answer: The answers in order are: Equal, 120°, Equal, 120°, Equal, no

Step-by-step explanation:

The positive sequence components have equal magnitudes and 120° phase displacements in positive sequence.  Their phase sequence is same as that of the system one. Also their phase rotations is same like the system.

The negative sequence components have equal magnitudes with same 120° phase displacements. Their phase sequence is opposite to that of system but their phase rotation is same like the system.

Zero sequence components have equal magnitude with no phase displacement. They behave like negative sequence in terms of phase sequence and phase rotation.

Answer:

Equal, 120°, Equal, 120°, Equal, no

Step-by-step explanation:

Determine the values of r for which the given differential equation has solutions of the form y = tr for t > 0. (Enter your answers as a comma-separated list.) t2y'' − 2ty' + 2y = 0

Answers

Answer:

The only solution is r=2 or r=1

Step-by-step explanation:

Check the attachment

Final answer:

To determine the values of r for which the given differential equation has solutions of the form y = tr for t > 0, substitute y = tr into the given differential equation and solve for r. The values of r that satisfy the equation are r = 1.

Explanation:

To determine the values of r for which the given differential equation has solutions of the form y = tr for t > 0, we need to substitute y = tr into the given differential equation and solve for r.

First, we find the first and second derivatives of y = tr:

y' = r

y'' = 0

Substituting these derivatives into the differential equation, we get:

t2(0) - 2t(r) + 2(tr) = 0

Simplifying the equation, we have:

(2 - 2r)t = 0

This equation is satisfied when t = 0 or r = 1. Therefore, the values of r for which the given differential equation has solutions of the form y = tr for t > 0 are r = 1.

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60% of all vehicles examined at a certain emissions inspection station pass the inspection. Assuming that successive vehicles pass or fail independently of one another, calculate the probability that at least one of the next three vehicles fail. (Give your answer as a decimal number with 3 digits of precision.)

Answers

Answer:

60%

Step-by-step explanation:

The percentage does not change.

Probability at least one of next 3 vehicles fail inspection: approximately 0.784 (to 3 decimal places).

To find the probability that at least one of the next three vehicles fail, we can calculate the probability of the complementary event, i.e., the probability that all three vehicles pass, and then subtract it from 1.

Given that 60% of vehicles pass the inspection, the probability that one vehicle fails the inspection is 1 - 0.60 = 0.40.

Since the vehicles pass or fail independently, the probability that all three vehicles pass is:

[tex]\[0.60 \times 0.60 \times 0.60 = 0.216\][/tex]

Now, the probability that at least one vehicle fails is:

[tex]\[1 - 0.216 = 0.784\][/tex]

So, the probability that at least one of the next three vehicles fail is approximately [tex]\(0.784\)[/tex] (to 3 decimal places).

A small business makes 3-speed and 10-speed bicycles at two different factories. Factory A produces 16 3-speed and 20 10-speed bikes in one day while factory B produces 12 3-speed and 20 10- speed bikes daily. It costs $1000/day to operate factory A and $800/day to operate factory B. An order for 80 3-speed bikes and 140 10-speed bikes has just arrived How many days should each factory be operated in order to fill this order at a minimum cost? (Give your answers correct to two decimal places.) Factory A should be operated Factory B should be operated days. days. What is the minimum cost? (Give your answer correct to the nearest dollar.)

Answers

Answer:

Factory A should be operated 6.11 days

Factory B should be operated 6.88 days

The minimum cost for factory A is $6,110

The minimum cost for factory B is $5,504

Step-by-step explanation:

Factory A

Daily production: 16 3-speed and 20 10-speed bikes

Total daily production = 16+20 = 36 speed bikes

Order: 80 3-speed and 140 10-speed bikes

Total order = 80+140 = 220 speed bikes

Number of days = 220/36 = 6.11 days

Cost per day = $1,000

Minimum cost for 6.11 days = $1000 × 6.11 = $6,110

Factory B

Daily production: 12 3-speed and 20 10-speed bikes

Total daily production = 12+20 = 32 speed bikes

Total order = 220 speed bikes

Number of days = 220/36 = 6.88 days

Cost per day = $800

Cost for 6.88 days = $800 × 6.88 = $5,504

Final answer:

The business should operate Factory A for about 2.92 days and Factory B for about 4.17 days to fill the order at a minimum cost of $7148.

Explanation:

This problem can be solved using Linear Programming, a mathematical model used in optimization problems. Suppose we let A be the number of days factory A operates and B be the number of days factory B operates. The cost to operate the factories is given by the equation C = 1000A + 800B.

The constraints are as follows:

Factory A produces 16 3-speed bikes per day and factory B produces 12, so 16A + 12B ≥ 80. Both factories produce 20 10-speed bikes per day, so 20A + 20B ≥ 140.

By solving these equations, you find that Factory A should be operated for about 2.92 days and Factory B should be operated for 4.17 days, giving a minimum cost of about $7148.

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Suppose you and your 4 friends (5 people) are dressing up as the 6 main characters of the first Avengers movie: Iron Man, Hulk, Thor, Black Widow, Captain America and Hawkeye. (each question is independent of the others.) How many ways can you do this if all 5 people dress up as a different character?

Answers

Answer:

720

Step-by-step explanation:

If every person has to choose a different character, the first person to choose a character has 6 options, the second has 5, the third has 4, the fourth has 3, and the last person has only two options. Therefore, the total number of ways you can do this if all 5 people dress up as a different character is:

[tex]n=6*5*4*3*2\\n=720[/tex]

There are 720 ways.

Final answer:

There are 720 different ways for 5 people to dress up as the 6 main Avengers characters; this combinatorics problem uses permutations to find the answer.

Explanation:

Combinations for Avengers Characters

The question is about calculations of combinations, which falls under the subject of Mathematics. More specifically, this is a combinatorics problem that can typically be found at a High School level. We want to find out how many different ways 5 people can dress up as any of the 6 main Avengers characters, assuming each person dresses up as a different character. To solve this, we can use the concept of permutations because the order in which we assign the characters to the 5 friends does matter.

In this case, we have 6 characters to choose from, and we want to assign these characters to 5 friends. We are therefore looking for the number of permutations of 6 characters taken 5 at a time, which is calculated using the formula:

P(n, k) = n! / (n - k)!

Here, 'n' is the total number of characters, and 'k' is the number of people to dress up. Therefore, we have:

P(6, 5) = 6! / (6 - 5)! = 6! / 1! = 720 / 1 = 720

There are 720 different ways for the 5 friends to dress up as the Avengers characters.

Vectors are quantities that possess both magnitude and direction. In engineering problems, it is best to think of vectors as arrows, and usually it is best to manipulate vectors using components. In this tutorial, we consider the addition of two vectors using both of these techniques. Consider two vectors AAA_evec and BBB_evec that have lengths AAA and BBB, respectively. Vector BBB_evec make

Answers

Answer:

Check below

Step-by-step explanation:

Vectors are quantities that possess both magnitude and direction. In engineering problems, it is best to think of vectors as arrows, and usually it is best to manipulate vectors using components. In this tutorial, we consider the addition of two vectors using both of these techniques. Consider two vectors [tex]\vec{A}[/tex]and [tex]\vec{B}[/tex] that have lengths A and B, respectively. Vector [tex]\vec{B}[/tex] makes an angle?

1) Vector [tex]\vec{B}[/tex] makes an angle?

Yes, it does. Vector [tex]\vec{B}[/tex] makes an angle with [tex]\vec{A}[/tex], since both have the same origin and different direction.

2) From the direction of A.(Figure 1)In vector notation, the sum is represented by  [tex]\vec{C}=\vec{A}+\vec{B}[/tex]  where [tex]\vec{C}[/tex] is a new vector that is the sum of [tex]\vec{A}[/tex] and [tex]\vec{B}[/tex].  Find C, the length of C, which is the sum of A and B.

C is the resultant vector of this sum of vectors([tex](\vec{C}=\vec{A}+\vec{B})[/tex]

The length of c is found through the law of cosines, after projecting, vector a.

(Check 3rd picture)

2.2) The other technique to add vectors is to write them. As C is the resultant vector then we have

[tex]\vec{A}=\left \langle a_{1},a_{2} \right \rangle \vec{B}=\left \langle b_{1},b_{2} \right \rangle \vec{C}=\left \langle a_{1}+b_{1}, a_{2}+b_{2}\right \rangle[/tex]

Final answer:

In physics, vectors are quantities possessing both magnitude and direction. They can be represented as arrows on a graph, with their length and direction corresponding to the vector's magnitude and direction. Vectors are added geometrically using the head-to-tail method or analytically, where they are broken down into components, and these components are added separately.

Explanation:

This can be visualized as an arrow, where its length corresponds to the magnitude, and its direction is represented by the way the arrow points. Some examples of vectors include displacement, velocity, and force.

When adding vectors, there are two methods to consider: geometric or component wise method. The geometric method involves representing the vectors as arrows on a graph and adding them using the head-to-tail method. The component-wise method involves breaking down the vector into its x and y components, and adding these components separately.

For instance, if you have two vectors A and B, vector A can be broken down into its x and y components: A_x and A_y. Likewise, vector B can be broken down into B_x and B_y. Simply add corresponding components to yield the resultant vector, R_x = (A_x + B_x) and R_y = (A_y + B_y)

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How expensive is Maui? A newspaper gave the following costs in dollars per day for a random sample of condominiums located throughout the island of Maui. 88 50 66 60 360 55 500 71 41 350 60 50 250 45 45 125 235 65 60 110 (a) Compute the mean, median, and mode for the data. (Round your answers to two decimal places.)

Answers

Final answer:

The mean (average) of the data set is approximately 110.40, the median (the middle value when the data set is arranged in order from least to greatest) is 65, and there is no mode (the most frequently occurring number) in the data set.

Explanation:

The subject of your question is Mathematics, specifically in the field of Statistics. To compute the mean, median, and mode, you would do the following:

Add up all numbers in the data set and divide by the number of items in that set. This is the Mean. Arrange the data set from smallest to largest and find the middle value. If there is an even number of items in the data set, the median is the average of the middle two numbers. This is the Median. The number that appears most frequently in your data set is the Mode.

For the given data set your mean is approximately 110.40 , the median is 65 and there is no mode as no numbers in the data set are repeated.

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What is the present value of a $50,000 decreasing perpetuity beginning in one year if the discount rate is 7% and the payments decline by 4% annually?

Answers

Answer:

Present Value = $1666666.67

Step-by-step explanation:

Present Value of a Growing Perpuity is calculated using the following formula

PV =D/(r - g)

Where D = Dividend

r = Discount Rate

g = Growth rate

D = $50,000

r = 7%

r = 7/100

r = 0.07

g = 4%

g = 4/100

g = 0.04

PV = D/(r-g)

Becomes

PV = $50,000/(0.07-0.04)

PV = $50,000/0.03

PV = $1,666,666.67

So the Present Value of the perpuity is $1,666,666.67

On a test, 74% of the questions are answered correctly. If 111 questions are correct, how many questions are on the test?

Answers

Answer:

150

Step-by-step explanation:

You have to divide the correct answers (111) by the total amount of questions (x) in order to find the 74% (0.74)

As per the unitary method, there are 150 questions on the test.

Let's start by breaking down the information we have been given. We know that 74% of the questions on the test were answered correctly, and the number of questions answered correctly is 111.

Step 1: Convert Percentage to Decimal

To make calculations easier, we need to convert the percentage into a decimal. To do this, we divide 74 by 100, which gives us 0.74.

Step 2: Set Up the Equation

Now we can set up an equation to solve for the total number of questions on the test. Let's denote the total number of questions as "x". Since 74% of the questions were answered correctly, we can say that 0.74x questions were answered correctly.

Step 3: Solve for Total Questions

We are given that 111 questions were answered correctly. So, we can set up the equation:

0.74x = 111

Step 4: Solve for "x"

To solve for "x", we need to isolate it on one side of the equation. We can do this by dividing both sides of the equation by 0.74:

x = 111 / 0.74

x = 150

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