An experiment involves selecting a random sample of 256 middle managers at random for study.One item of interest is their mean annual income.The sample mean is computed to be $35,420 and the sample standard deviation is $2,050.What is the standard error of the mean?
A)$128.125
B)$138.36
C)$2,050
D)$8.01

Question

Quizplus · Accepted Answer

The standard error of the mean is the standard deviation of the sampling distribution of the mean. It is calculated by dividing the sample standard deviation by the square root of the sample size. In this case, the sample standard deviation is $2,050 and the sample size is 256. Therefore, the standard error of the mean is $2,050 / sqrt(256) = $128.125.

An Experiment Involves Selecting a Random Sample of 256 Middle