Question

Random samples of size 81 are taken from an infinite population whose mean and standard deviation are 200 and 18, respectively. The distribution of the population is unknown. The mean and the standard error of the sampling distribution of sample mean are

Select one:
a. 200 and 18
b. 9 and 2
c. 81 and 18
d. 200 and 2 Correct

Answer 1

D 200 and 2

Explanation:

standard error of the sampling distribution of sample mean is expressed using the formula;

Standard error of the mean = S/√n where;

S is the standard deviation

n is the sample size

Given

S = 18

n = 81

SEM = 18/√81

SEM = 18/9

SEM = 2

The mean of the distribution according to the question is 200.

Hence the mean and the standard error of the sampling distribution of sample mean are 200 and 2 respectively.