Question

What are the conditions for using the standard deviation formulasquare root p times 1 minus p divided by nwhen working with a sampling distribution of proportions?

Answer 1

In order to use the Normal approximation to the Binomial ...

np ≥ 5 and n(1-p) ≥ 5 [note: some textbooks use 10 instead of 5, check your book or notes]

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