the following are the monthly sales (in thousands of dollars) for a company in four regions of the country.

Does the data suggest that there is a difference in the mean monthly sales among the different regions?

1)

Identify the class​ width for the given Frequency Distribution Table

List -------------Frequency

10 to 14 -------------27

15 to 19 -------------35

20 to 24 -------------14

25 to 29 --------------2

30 to 34 --------------4

35 to 39 --------------2

40 to 44 --------------1

2)

Which measurement is the most accurate?

1. Mode

2. Mean

3. Range

4. Median

Calculate the present value of the following amounts assuming that the cash flow is received at the end of each specified period: 211

I appreciate if you can explain me step by step. Thank you.

Write a one-page essay on customer expectations. What are customers’ expectations when they walk into these places of business?

Choose any two:

Furniture store
Restaurant
Medical clinic
Pharmacy
Convenience store (e.g. 7-Eleven)

Reference your own experience and material from the text. Remember that spelling and grammar are important.

Some five courses are offered on campus in a semester. The group of students who take at least one of these courses consists of 155 students. There are 80 students registered in each course. For any two among these courses, there are precisely 40 students who take both of them. For any three of these courses, there are precisely 20 students who take all three of them. For any four among these courses, there are precisely 10 students who take every one of these four courses. How many students in this group take every one among the five courses in this memorable semester?

Identifying individuals with a high risk of Alzheimer’s disease usually involves a long series of cognitive tests. However, researchers have developed a 7-Minute Screen, which is a quick and easy way to accomplish the same goal. The question is whether the 7-Minute Screen is as effective as the complete series of tests. To address this question, Ijuin et al. (2008) administered both tests to a group of patients and compared the results. The following data represent results similar to those obtained in the study.

A. Compute the Pearson Correlation Coefficient for these data.

r =

B. The correlation is

Medium and negative

Large and negative

Large and positive

Medium and positive

C. The null hypothesis for a two-tailed test is

The correlation between the scores on the 7-minute screen test and the scores on the cognitive series is significant

The correlation between the scores on the 7-minute screen test and the scores on the cognitive series is not significant

The correlation between the scores on the 7-minute screen test and the scores on the cognitive series is less than zero

The correlation between the scores on the 7-minute screen test and the scores on the cognitive series is different from zero

D. If we use a two-tailed test with α = .01, the critical r values are:

±0.666

±0.582

±0.798

±0.750

E. Your decision is:

Reject the null hypothesis and conclude that there is a significant correlation between the scores on the 7-minute screen test and the scores on the cognitive series

Fail to reject the null hypothesis and conclude that there is a significant correlation between the scores on the 7-minute screen test and the scores on the cognitive series

Reject the null hypothesis and conclude that there is no significant correlation between the scores on the 7-minute screen test and the scores on the cognitive series

Fail to reject the null hypothesis and conclude that there is no significant correlation between the scores on the 7-minute screen test and the scores on the cognitive series

A random sample of eight drivers insured with a company and having similar auto insurance policies was selected. The following table lists their driving experiences (in years) and monthly auto insurance premiums.

a. Does the insurance premium depend on the driving experience or does the driving experience depend on the insurance premium? Do you expect a positive or a negative relationship between these two variables?

b. Compute SSxx, SSyy, and SSxy.

c. Find the least squares regression line by choosing appropriate dependent and independent variables based on your answer in part a.

d. Interpret the meaning of the values of a and b calculated in part c.
e. Plot the scatter diagram and the regression line.
f. Calculate r and r2 and explain what they mean.
g. Predict the monthly auto insurance premium for a driver with 10 years of driving experience. h. Compute the standard deviation of errors.

For each exercise, answer the following along with any additional questions. Assume group variances are equal (unless the problem is ran via statistical software). |  Provide the null and alternative hypotheses in formal and plain language for appropriate two-tailed test (viz., dependent or independent) at the 0.05 significance level  Do the math and reject/accept null at a=.05. State your critical t value.  Explain the results in plain language.  Calculate the 95% confidence interval for the difference in means and state both formally and in plain language if appropriate.

Home Harvest, a local homeless support charity in the northeastern U.S. traditionally mails donation requests to previous donors in the last five years around Thanksgiving. A board member suggests e-mail might be more efficient and cheaper but there is concern an email would be seen as less personal and accrue lower donations. Home Harvest takes a random sample of sixteen regular personal donors (viz., have donated each of the last three years). Six receive an e-mail and eleven a letter for the next Thanksgiving. Donations in dollars are as follows:

E-mail: 40, 0, 60, 40, 70, 0

Letter: 110, 550, 120, 650, 0, 100, 120, 20, 110, 110, 100

A team of sports scientists want to know if having a dietitian as part of the staff is better at producing divisional basketball champions than current ad-libitum (as desired) nutritional practices. Of the ad-libitum, 12 were champions and 18 were non-champions. Of the dietician-tailored, 7 were champions and 8 were non-champtions. What can they conclude?

Choose the most correct answer.

Select one:

a. After performing a 2 x 2 chi square test, no significant difference between champion and non-champion basketball teams was found between the two dietary approaches (χ2 = 0.18, df = 1, p < .05).

b. After performing a 2 x 2 chi square test, no significant difference between champion and non-champion basketball teams was found between the two dietary approaches (χ2 = 0.18, df = 1, p > .05).

c. After performing a 2 x 2 chi square test, no significant difference between champion and non-champion basketball teams was found between the two dietary approaches (χ2 = 0.01, df = 1, p < .05).

d. After performing a 2 x 2 chi square test, a significant difference between champion and non-champion basketball teams was found between the two dietary approaches (χ2 = 0.01, df = 1, p < .05).

e. After performing a 2 x 2 chi square test, a significant difference between champion and non-champion basketball teams was found between the two dietary approaches (χ2 = 3.84, df = 1, p < .05).

The random sample shown below was selected from a normal distribution.

1010​,

44​,

77​,

66​,

77​,

22

Complete parts a and b.

a. Construct a

9595​%

confidence interval for the population mean

muμ.

left parenthesis nothing comma nothing right parenthesis3.113.11,8.898.89

​(Round to two decimal places as​ needed.)b. Assume that sample mean

x overbarx

and sample standard deviation

ss

remain exactly the same as those you just calculated but that are based on a sample of

nnequals=2525

observations. Repeat part a. What is the effect of increasing the sample size on the width of the confidence​ intervals?The confidence interval is

left parenthesis nothing comma nothing right parenthesisnothing,nothing.

​(Round to two decimal places as​ needed.)