Random samples of size 81 are taken from an infinite population whose mean and standard deviation are 45 and 9, respectively. The mean and standard error of the sampling distribution of the sample mean are:
A)9 and 45.
B)45 and 9.
C)81 and 45.
D)45 and 1.

Question

Quizplus · Accepted Answer

The mean of the sampling distribution of the sample mean is equal to the population mean, which is 45. The standard error of the sampling distribution is calculated as the population standard deviation divided by the square root of the sample size, which is 9 / sqrt(81) = 9 / 9 = 1.

Random Samples of Size 81 Are Taken from an Infinite