A sample of 200 elements from a population with a known standard deviation is selected. For an interval estimation of μ, the proper distribution to use is the
A) normal distribution.
B) t distribution with 200 degrees of freedom.
C) t distribution with 201 degrees of freedom.
D) t distribution with 199 degrees of freedom.

Question

Quizplus · Accepted Answer

When the population standard deviation is known and a sample size of 30 or more is being used, the appropriate distribution to use for interval estimation of the population mean is the normal distribution. In this case, the sample size is 200 which is greater than 30, and the population standard deviation is known, so the appropriate distribution to use is the normal distribution. Choice A is the correct answer.

A Sample of 200 Elements from a Population with a Known