Question

Sales personnel for RH Educational Systems submit weekly reports listing the customer contacts made during the...

Sales personnel for RH Educational Systems submit weekly reports listing the customer contacts made during the week. A sample of 65 weekly reports showed a sample mean of 19.1 customer contacts per week. The sample standard deviation was 5.4.

1. Determine a 90% confidence interval for the population mean number of weekly customer contacts for the sales personnel. Round the endpoints of the interval to 2 decimal places.

2. Determine a 95% confidence interval for the population mean number of weekly customer contacts for the sales personnel. Round the endpoints of the interval to 2 decimal places.

Homework Answers

Answer #1

it is given that the sample size is n = 65, mean = 19.1 and standard deviation is s = 5.4

sample size is large enough, i.e. more than 30, so we will assume that the sample standard deviation is equal to the population standard deviation

(A) z score for 90% confidence interval is z = 1.645 (using the z distribution table)

confidence interval =

this implies

(B)

z score for 95% confidence interval is z = 1.96 (using the z distribution table)

confidence interval =

this implies

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Sales personnel for Skillings Distributors submit weekly reports listing the customer contacts made during the week....
Sales personnel for Skillings Distributors submit weekly reports listing the customer contacts made during the week. A sample of 66 weekly reports showed a sample mean of 17.5 customer contacts per week. The sample standard deviation was 4.2. Provide a 90% confidence interval for the population mean number of weekly customer contacts for the sales personnel. (Round your answers to two decimal places.)   contacts/week to    contacts/week Provide 95% confidence interval for the population mean number of weekly customer contacts for...
Sales personnel for Skillings Distributors submit weekly reports listing the customer contacts made during the week....
Sales personnel for Skillings Distributors submit weekly reports listing the customer contacts made during the week. A sample of 85 weekly reports showed a sample mean of 18.5 customer contacts per week. The sample standard deviation was 5.6. Provide 90% and 95% confidence intervals for the population mean number of weekly customer contacts for the sales personnel. 90% Confidence interval, to 2 decimals: ( ,  ) 95% Confidence interval, to 2 decimals: What is the 95% confidence interval for the population...
Sales personnel for Skillings Distributors submit weekly reports listing the customer contacts made during the week....
Sales personnel for Skillings Distributors submit weekly reports listing the customer contacts made during the week. A sample of 85 weekly reports showed a sample mean of 17.5 customer contacts per week. The sample standard deviation was 5.1. Provide 90% and 95% confidence intervals for the population mean number of weekly customer contacts for the sales personnel. 90% confidence interval, to 2 decimals: (____,____) 95% confidence interval, to 2 decimals: (____,_____)
Sales personnel for Skillings Distributors submit weekly reports listing the customer contacts made during the week....
Sales personnel for Skillings Distributors submit weekly reports listing the customer contacts made during the week. A sample of 85 weekly reports showed a sample mean of 18.5 customer contacts per week. The sample standard deviation was 5.6. Provide 90% and 95% confidence intervals for the population mean number of weekly customer contacts for the sales personnel. 90% Confidence interval, to 2 decimals: 95% Confidence interval, to 2 decimals:
Sales personnel for Skillings Distributors submit weekly reports listing the customer contacts made during the week....
Sales personnel for Skillings Distributors submit weekly reports listing the customer contacts made during the week. A sample of 85 weekly reports showed a sample mean of 19.5 customer contacts per week. The sample standard deviation was 5.8. Provide 90% and 95% confidence intervals for the population mean number of weekly customer contacts for the sales personnel. 90% Confidence, to 2 decimals: ( _ , _ ) 95% Confidence, to 2 decimals: ( _ , _ )
Sales personnel for Skillings Distributors submit weekly reports listing the customer contacts made during the week....
Sales personnel for Skillings Distributors submit weekly reports listing the customer contacts made during the week. A sample of 85 weekly reports showed a sample mean of 17.5 customer contacts per week. The sample standard deviation was 5.5. Provide 90% and 95% confidence intervals for the population mean number of weekly customer contacts for the sales personnel. 90% Confidence, to 2 decimals: ( , ) 95% Confidence, to 2 decimals: ( , )
Mr. James McWhinney, president of Daniel-James Financial Services, believes there is a relationship between the number...
Mr. James McWhinney, president of Daniel-James Financial Services, believes there is a relationship between the number of client contacts and the dollar amount of sales. To document this assertion, Mr. McWhinney gathered the following sample information. The x column indicates the number of client contacts last month and the ycolumn shows the value of sales ($ thousands) last month for each client sampled. (Round your answers to 3 decimal places.) Number of Contacts, x Sales ($ thousands), y Number of...
A hair salon in Cambridge, Massachusetts, reports that on seven randomly selected weekdays, the number of...
A hair salon in Cambridge, Massachusetts, reports that on seven randomly selected weekdays, the number of customers who visited the salon were 72, 55, 49, 35, 39, 23, and 77. It can be assumed that weekday customer visits follow a normal distribution. [You may find it useful to reference the t table.] a. Construct the 90% confidence interval for the average number of customers who visit the salon on weekdays. (Round intermediate calculations to at least 4 decimal places, "sample...
Quality Progress, February 2005, reports on improvements in customer satisfaction and loyalty made by Bank of...
Quality Progress, February 2005, reports on improvements in customer satisfaction and loyalty made by Bank of America. A key measure of customer satisfaction is the response (on a scale from 1 to 10) to the question: "Considering all the business you do with Bank of America, what is your overall satisfaction with Bank of America?" Here, a response of 9 or 10 represents "customer delight." Suppose that the survey selected 260 customers. Assume that 45% of Bank of America customers...
The manager of The Cheesecake Factory in Boston reports that on six randomly selected weekdays, the...
The manager of The Cheesecake Factory in Boston reports that on six randomly selected weekdays, the number of customers served was 165, 135, 95, 145, 125, and 265. She believes that the number of customers served on weekdays follows a normal distribution. Construct the 90% confidence interval for the average number of customers served on weekdays. (You may find it useful to reference the t table. Round intermediate calculations to at least 4 decimal places, "sample mean" and "sample standard...