A national fast food chain, with thousands of franchise locations, needed to aud

Question

A national fast food chain, with thousands of franchise locations, needed to audit the books at each location. They first selected a sample of 50 locations and performed the audit. They determined that a 95% confidence interval for the mean time to complete an audit is: (28.4 hours, 53,7 hours)

Answer the following questions, "yes," "no," or "cannot tell" and justify your answer.

(a) Does the population mean lie in the interval (28.4, 52.7)

(b) Does the sample mean lie in ther interval (28.4, 52.7)

(c) For a future sample of 50 franchise locations, will the sample mean fall in the interval (28.4, 52.7)

(d) Does 95% of the sample data lie in the interval (28.4, 52.7)

Explanation / Answer

Hi! I assume that the 53.7 in the paragraph is just a typo for 52.7, because that makes more sense. Thanks!

(a) Does the population mean lie in the interval (28.4, 52.7)

Cannot tell. We are 95% confident that it is inside, though.

(b) Does the sample mean lie in ther interval (28.4, 52.7)

Yes, indeed. The sample mean is always the middle of the interval.

(c) For a future sample of 50 franchise locations, will the sample mean fall in the interval (28.4, 52.7)

Cannot tell. Samples vary.

(d) Does 95% of the sample data lie in the interval (28.4, 52.7)

No. This is a measure of the population mean, not the individual values.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.