Author Question: A manager of the credit department for an oil company would like to determine whether the mean ... (Read 151 times)

ss2343 · **on:** Jun 24, 2018

A manager of the credit department for an oil company would like to determine whether the mean monthly balance of credit card holders is equal to 75. An auditor selects a random sample of 100 accounts and finds that the mean owed is 83.40 with a sample standard deviation of 23.65. If you wanted to test whether the mean balance is different from 75 and decided to reject the null hypothesis, what conclusion could you reach?

A) There is evidence that the mean balance is not 75.
B) There is no evidence that the mean balance is 75.
C) There is no evidence that the mean balance is not 75.
D) There is evidence that the mean balance is 75.

Question 2

A manager of the credit department for an oil company would like to determine whether the mean monthly balance of credit card holders is equal to 75. An auditor selects a random sample of 100 accounts and finds that the mean owed is 83.40 with a sample standard deviation of 23.65. If you were to conduct a test to determine whether the auditor should conclude that there is evidence that the mean balance is different from 75, which test would you use?

A) Z test of a population mean B) t test of population mean
C) Z test of a population proportion D) t test of a population proportion