As a rule of thumb, the sampling distribution of the sample proportions can be approximated by a normal probability distribution whenever
A)np 5
B)n(1 - p) 5 and n 30
C)n 30 and (1 - p) = 0.5
D)None of these alternatives is correct.

Question

As a rule of thumb, the sampling distribution of the sample proportions can be approximated by a normal probability distribution whenever
A)np 5 
B)n(1 - p) 5 and n 30 
C)n 30 and (1 - p) = 0.5 
D)None of these alternatives is correct.

Quizplus · Accepted Answer

The sampling distribution of the sample proportions can be approximated by a normal probability distribution when the sample size is sufficiently large (n≥30) and when np≥5 and n(1-p)≥5.

As a Rule of Thumb, the Sampling Distribution of the Sample