SOLUTION: Can someone please answer this and help me understand how to calculate? Thank you. According to a recent poll, 16.2% of credit cardholders in the United States have used their c

Algebra ->  Probability-and-statistics -> SOLUTION: Can someone please answer this and help me understand how to calculate? Thank you. According to a recent poll, 16.2% of credit cardholders in the United States have used their c      Log On


   

Question 265571: Can someone please answer this and help me understand how to calculate? Thank you.
According to a recent poll, 16.2% of credit cardholders in the United States have used their credit card to make a purchase on the internet. You will be asked to identify how large a sample should be taken if the true proportion is to be estimated to within 1.5% at the 95% reliability level? You may use the sample proportion in the calculation of the sample size.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
According to a recent poll, 16.2% of credit cardholders in the United States have used their credit card to make a purchase on the internet. You will be asked to identify how large a sample should be taken if the true proportion is to be estimated to within 1.5% at the 95% reliability level? You may use the sample proportion in the calculation of the sample size.
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Formula:
Since E = z*sqrt[pq/n]
sqrt(n) = (z/E)*sqrt(pq)
n = (z/E)^2(pq)
Your problem:
n = (1.96/0.015)^2*(0.162*0.83.8)
n = 2317.87
Round up to n = 2318
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Cheers,
Stan H.