An infinite population has a mean of 40 and a standard deviation of 15.A sample of size 100 is taken at random from this population.The standard error of the sample mean equals:
A) 15
B) 15/$\surd$100
C) 15/100
D) None of these choices.

Question

Quizplus · Accepted Answer

The standard error of the sample mean is calculated by dividing the population standard deviation by the square root of the sample size.

Standard error of the sample mean = σ/√n

where σ = population standard deviation and n = sample size

In this case, σ = 15 and n = 100

Standard error of the sample mean = 15/√100 = 15/10 = 1.5

Therefore, the correct answer is B) 15/√100 or 15/10.

An Infinite Population Has a Mean of 40 and a Standard