The diameter of small Nerf balls manufactured at a factory in China is expected to be approximately normally distributed with a mean of 5.2 inches and a standard deviation of .08 inches.Suppose a random sample of 20 balls is selected.Calculate the standard deviation of the sampling distribution of the sample mean.
A)5.2
B)0.018
C)0.08
D)0.063

Question

Quizplus · Accepted Answer

The standard deviation of the sampling distribution of the sample mean is equal to the standard deviation of the population divided by the square root of the sample size. In this case, the standard deviation of the population is 0.08 inches and the sample size is 20. Therefore, the standard deviation of the sampling distribution of the sample mean is 0.08 / sqrt(20) = 0.018 inches.

The Diameter of Small Nerf Balls Manufactured at a Factory