A researcher conducted a study of the access speed of 45 hard drives and concluded that his maximum error of estimate was 24. If he were to conduct a second study to reduce
The maximum error of estimate to 6, about how many hard drives should he include in his
New sample?
A) 720
B) 90
C) 45
D) 180

Question

Quizplus · Accepted Answer

The maximum error of estimate is inversely proportional to the square root of the sample size. To reduce the error by a factor of 4 (from 24 to 6), the sample size needs to be increased by a factor of 16 (since 4^2 = 16). Therefore, multiplying the original sample size of 45 by 16 gives 720.

A Researcher Conducted a Study of the Access Speed of 45