SOLUTION: A person wants to be 90% confident and be accurate within 5% of true proportion. Please help me find minimum sample size.

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Question 932099: A person wants to be 90% confident and be accurate within 5% of true proportion. Please help me find minimum sample size.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi

E = .05,  90% confident...then z = 1.645 (See Below)

n = [z*SD/E]^2

0r

n = p(1-p)(z/E)^2  (Depending on Info given)

IF no other INof Given:

n = .50(.50)(z/E)^2

Always round UP to NEXT Integer

 CI	z = value

90%	z =1.645

92%	z = 1.751

95%	z = 1.96

98%	z = 2.326

99%	z = 2.576