A simple random sample of 100 observations was taken from a large population. The sample mean and the standard deviation were determined to be 1234 and 120 respectively. The standard error of the mean is
A) 1234 ± 120.
B) 120.
C) 1.2.
D) 12.

Question

Quizplus · Accepted Answer

The formula for standard error of the mean is:
standard error = standard deviation / square root of sample size
standard error = 120 / √100
standard error = 12

A Simple Random Sample of 100 Observations Was Taken from a Large