The student newspaper at a college asks a simple random sample of 250 undergraduates, "Do you favor eliminating supplemental fees for lab courses?" In all, 150 of the 250 are in favor of eliminating such fees.
Suppose that (unknown to you) 55% of all undergraduates favor eliminating supplemental fees for lab courses. If you took a very large number of simple random samples of size n = 250 from this population, the sampling distribution of the sample proportion p would be approximately normal with
A) mean 0.55 and standard deviation 0.015.
B) mean 0.60 and standard deviation 0.06.
C) mean 0.55 and standard deviation 0.06.
D) mean 0.60 and standard deviation 0.03.
E) mean 0.55 and standard deviation 0.03.

Question

Quizplus · Accepted Answer

The sampling distribution of the sample proportion p is approximately normal with a mean equal to the population proportion (0.55) and a standard deviation calculated as sqrt[(0.55)(0.45)/250] ≈ 0.03.

The Student Newspaper at a College Asks a Simple Random