In a study on the physical activity of people, researchers measured overall physical activity as the total number of registered movements (counts) over a period of time and then computed the number of counts per minute (cpm) for each subject. The study revealed that the overall physical activity of obese people has a mean of μ=322cpm and a standard deviation σ=92cpm. In a random sample of 100 obese people, consider x ̅, the sample mean counts per minute.

Now suppose we are interested in the total activity (Σcpm) of a random sample of 25 obese people. Answer the following questions on a separate sheet of paper and upload to "Quiz Ch. 7 Free Response Answer":

a) Write a distribution statement that describes this new study of total activity (Σcpm).

b) Find the probability that the total cpm for 25 obese people is less than 7,500 cpm.

c) Sketch the graph, labeling and scaling the horizontal axis. Shade the region corresponding to the probability in part b.

d) How likely is it that those 25 people will collectively register more than 9,000 cpm? Explain how you came to that conclusion.

The Department of Navy has been downsizing and must find cost savings opportunities to meet mandated congressional budget cuts. One suggestion under consideration is to change the makeup of the content of Navy sea rations, the canned food supplies containing certain minimum daily requirements (MDR) of Vitamin A, Vitamin D, iron, and other nutrients, which combat troops carry into battle. The current supplier of Navy sea rations is Texfoods. A two-ounce portion of their product supplies 20% of the required amount of Vitamin A, 25% of the MDR of Vitamin D, and 50% of the required amount of iron. Each two-ounce portion cost the Navy $0.60. Because all minimum standards for nutrient must be met in each serving, the current sea ration container must contain 10 ounces of the Texfoods product (to meet the MDR of Vitamin A). This cost the Navy $3.00 (5 * $0.60 = $3.00) per serving. A new supplier, Calration, is pushing the Navy to switch to their product. A two-ounce portion of Calration cost $0.50, a saving of $0.10 per two-ounce portion. A two-ounce portion of Calration provides 50% of the MDR for Vitamin A, 25% of the requirement for Vitamin D, but only 10% of the MDR for iron. If a switch is made to Calration the sea ration container would have to contain 20 ounces in order to meet the MDR for iron. The cost to the Navy would be $5.00 (10 * $0.50) per serving. In your new position as Chief Procurement Officer, Northern Fleet Command you suggested mixing the two products might meet the nutrient standards at a lower cost than the current $3 per serving. While the Navy has always prided itself on the quality of foods served, taste has not been a worry for Congress; hence, mixing the rations, either by combining them or by packing a portion of each, is an acceptable alternative. You have been given instructions to evaluate the data.

Prepare a report for congress that recommends the number of two-ounce portions of Texfoods and Calrations to include in a single serving of sea rations that will provide the MDR of Vitamins A and D and iron (it is not necessary to know the MDR of these items [Why?]). Congress is interested in the preserving cost of your serving and the Navy might be interested in the total weight of the serving (Why?). Senator Joe Ask Questions will want to know if your proposed mixture supplies an excess of either Vitamin A, D, or iron. Also, Senator Meg Curious will want to know what might happen if Texfoods or Calration changes their pricing; does your proposed mixture remain the same. Address your report to Members of Congress, Naval Food Committee. Be sure to follow the quantitative analysis approach in your report.

The CEO of a company wants to estimate the percent of employees that use company computers to go on Facebook during work hours. He selects a random sample of 200 of the employees and finds that 76 of them logged onto Facebook that day. Construct a 95% confidence interval for the population proportion.

Answer the following questions in the Answer box.

a. i) Sample proportion = ?    a. ii) critical value Z = ? a. iii) Standard error = ?    a. iv) Margin of error = ?    a. v) Lower limit = ?    a. vi) upper limit = ?

a. The weight of 8 persons (in LB) are: 138,143,141, 139, 152, 148, 160 and 267. Find the average weight using the suitable form of average. Give reason for your choice.

b.

The above data consists of two outliers 234 and 302, due to which the A.M. is greatly affected. Treating outliers as one group and remaining observations as second group compute the following:

i. arithmetic mean of individual groups and combined group

ii. standard deviations of individual groups and combined standard deviation of both groups, also interpret your answer

Hello:

I am working on some homework problems for decision modeling. Here is the question: The weekly deman for a slow moving product has the following probability mass function:

Demand, x Probability f(x)

0 0.2

1 0.4

2 0.3

3 0.1

4 or more 0

Use VLOOKUP to generate 25 random variates from this distribution. I know i have to use RAND and VLOOKUP I just cannot get it to give me 25 random numbers. Thank you for any help you can give me.

A realtor is interested to compare the average cost of a 3 bedroom home in three different cities.   Prices from a sample of homes in each city are collected and shown in the dataset shown below (data is shown in thousands of dollars).

The realtor is interested to know if the prices of the average 3 bedroom home are statistically the same for the three cities.    Use a significance level of 5%.

The realtor has confirmed that the samples were randomly selected and independent, and the populations have normal distribution and the population variances are equal.  

(a) calculate the Test Statistic for this example (round your answer to 2 decimal places)

(b) calculate the P-value for this example (round your answer to 2 decimal places)

"Housing Prices in Atlanta"   Housing Prices in Seattle   Housing Prices in Miami
344 331 295
332 273 295
360 378 317
332 374 293
301 329    333
312 372 295
361 320 324
355 292   406
360 289 312
269 363 357
277 342 385
376 322 349
360 354 422
398 342 361
298 342 337
314   323 385
341 336 337
340 367 334
390 419 328
348 320 347

An urn contains 7 red and 10 blue balls. If 4 balls are to be randomly selected without replacement, what is the probability that the first 2 selected are red and the last 2 selected are blue? Explain each step ?

A waitress believes the distribution of her tips has a model that is slightly skewed to the left​, with a mean of ​$9.20 and a standard deviation of ​$5.80. She usually waits on about 30 parties over a weekend of work.
​A) Estimate the probability that she will earn at least ​$350.
​B) How much does she earn on the best 10​% of such​ weekends?

Alexandra Marcus, manager of the Sky Club Hotel, has requested your assistance on a queuing issue to improve the guest service at the hotel. Alexandra Marcus is considering how to restructure the front desk to reach an optimal level of staff efficiency and guest service. Observation of arrivals during the peak check-in time of 3:00PM to 5:00PM shows that an average of 80 guests arrive each hour. It takes an average of 3 minutes for the front-desk clerk to register each guest. At present, the hotel has five clerks on duty, each with a separate waiting line.

PLEASE SHOW CALCULATIONS!!

a. Average utilization rate of a server (p)

b. The probability of no. customers in the system (Po)

c. Average number of customers in the system (L)

d. Average time in the system (W)

e. Average waiting in line (Wq)

f. Average number of customers in line waiting Lq

In a study comparing banks in Germany and Great Britain, a sample of 145 matched pairs of banks was formed. Each pair contained one bank from Germany an done from Great Britain. The pairings were made in such a way that the two members were as similar as possible in regard to such factors as size anda ge (mattched samples). The ratio of total loans outstanding to total assets was calculated for each of the banks. Fort his ratio, the sample mean difference (German – Great Britain) was 0.0518, and the sample standard deviation of the differences was 0.3055. Test against a two-sided alternative, the null hypothesis that the two population means are equal.

For this problem clearly state the

a) null and alternative hypothesis,

b) decision rule and

c) conclusion.

Publisher is interested in the effects of sales of college texts that include more than 100 data files. The Publisher plans to produce 20 texts in the business area and randomly chooses 10 to have more than 100 fileas. The remaining 10 are produced with at most 100 files. For those with mıre than 100, first-year sales averaged 9254 and the sampel standard deviation was 2107. Fort he boks with at most 100 files, average first-year sales were 8167, and sample standard deviation was 1681. Assuming the two population distributions are normal, test the null hypothesis that the population variances are equal against the alternative that the population variance is higher for books with more than 100 files.

For this problem clearly state the

a) null and alternative hypothesis,

b) decision rule and

c) conclusion.

The weekly statistics about number of passengers (Y in 1000s) per week in terms of the number electric train cars (X) were collected through 30 weeks. The data were collected to assess the relationship between the number of passengers and the number of electric train cars. The process of data indicates the following results:

ΣX= 2589, ΣY= 762.748, ΣX^²=373055

ΣY^²=34905.9243 ΣYX= 112979.248

Σ(Y-Ya)*(X-Xa)= 14241.5194,

Σ(X-Xa)^² =37908.95

SST= 5816.7, SSE= 466.488, SSX= 37908.95

Where: Xa stands for Average of X

Ya Stands for Average of Y

For any hypothesis testing undertaken in this model, use the level of significance α=5%

1. What is the expected sign of the independent variable?
2. Develop the linear regression model Using the least square method of estimation and interpret the meaning of the intercept and the regression coefficient.
3. Compute R² and interpret its meaning
4. Is the number of passengers sensitive to the number of electric train cars?
5. Compute the confidence interval of regression coefficient and interpret its meaning
6. Forecast the dependent variable if the independent variable is 165.
7. Find out and interpret the confidence interval of the predicted value computed in question (6).
8. Based on the previous questions, how well the model fits to this phenomenon

A medical school claims that more than 28% of its students plan to go into general practice. It is found that among a random sample of 130 of the school's students, 33% of them plan to go into general practice. Using a 0.05 significance level, test the claim that more than 28% of the medical school’s students plan to go into general practice.

a) Write the null and alternative hypotheses.

b) Determine the P-value.

c) Should you Reject H0 or Fail to reject H0?

d) Write a sentence to state your final conclusion.

What is the best description of a hypothesis test?

Select one:

a. A tool for comparing population parameters inferred from samples

b. Dissecting the data

c. Help in solving problems

d. Breaking up the problem

Which hypothesis test is similar to the 1 sample t-test but is used when the data set is non-normal?

Select one:

a. 1- sample sign

b. Kruskal-Wallis

c. Friedman

d. Mann-Whitney

Which statements is correct about the Capability Analysis shown?

Select one:

a. From this study we can predict that this process will produce less than 100 parts per million that are outside of the specification limits

b. The process has a problem with centering.

c. The parts have a mean average diameter between 4 mm and 4.9 mm

d. The process needs significant improvements to be in control

In posing the question “Do you believe in aliens?”, 54% +5% of the men responded that they do while 33% +5% of women responded that they believe in aliens. a.for the Men: Identify the margin of error and explain what it means. b.For the Women:Give the actual interval their statistic represents. c.Is the difference in views between genders statistically significant? Explain