Question

A research worker wants to determine the average time it takes a mechanic to rotate the tires of a car, and she wants to be able to assert with confidence that the mean of her sample is off by at most 0.4 minutes. If she can presume from past experience that the actual time follows a distribution with a standard deviation of 1.5 minutes, how large the sample will she have to take? 55 38 39 54

          A research worker wants to determine the average time it takes a mechanic to rotate the tires of a car, and she wants to be able to assert with confidence that the mean of her sample is off by at most 0.4 minutes. If she can presume from past experience that the actual time follows a distribution with a standard deviation of 1.5 minutes, how large the sample will she have to take?

55
38
39
54

A research worker wants to determine the average time it takes a mechanic to rotate the tires of a car, and she wants to be able to assert with confidence that the mean of her sample is off by at most 0.4 minutes. If she can presume from past experience that the actual time follows a distribution with a standard deviation of 1.5 minutes, how large the sample will she have to take?

55
38
39
54

Added by Christina C.

Elementary Statistics a Step by Step Approach

Allan G. Bluman 9th Edition

Instant Answer

Solved by Expert Anna D.

08/18/2023

Step 1

If not specified, assume a 95% confidence interval. Show more…

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A research worker wants to determine the average time it takes a mechanic to rotate the tires of a car, and she wants to be able to assert with confidence that the mean of her sample is off by at most 0.4 minutes. If she can presume from past experience that the actual time follows a distribution with a standard deviation of 1.5 minutes, how large the sample will she have to take?