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) 45 and 9
B) 45/81 and 9/81
C) 45 and 9/$\surd$81
D) 45/$\surd$81 and 9/$\surd$81

Question

Quizplus · Accepted Answer

The mean of the sampling distribution of the sample mean is the same as the population mean, which is 45. The standard error is the population standard deviation divided by the square root of the sample size, which is 9/√81 = 1.

Random Samples of Size 81 Are Taken from an Infinite √\surd√

Random Samples of Size 81 Are Taken from an Infinite $\surd$