<PRE><B>Question 633435</B>
Preliminary studies indicate that about 40% of those surveyed believe what is shown in commercials. What is the minimum number of consumers that should be sampled by the advertiser to be 95% confident that their estimate will fall within 1% of the true population proportion? 
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Since E = z*sqrt(pq/n)
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n = [z/E]^2*pq
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Your Problem:
n = [1.96/0.01]^2*0.4*0.6
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n = 9220 when rounded up
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Cheers,
Stan H.</PRE>