SOLUTION: Parle Agro India Pvt. Ltd. wants to conduct a survey to find whether more people prefer Frooti to Slice. It was estimated before the survey that half of the population prefers Froo

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Question 1190678: Parle Agro India Pvt. Ltd. wants to conduct a survey to find whether more people prefer Frooti to Slice. It was estimated before the survey that half of the population prefers Frooti and half prefers Slice. How large a sample would Parle Agro India Pvt. Ltd. have to take to estimate the proportion of people who prefer Frooti within +/- 0.03 of the actual value, with 98% confidence? considering Z value is 2
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
error=z*sqrt(p*(1-p)/n)
0.03=2*sqrt(0.25/n)
0.0009=4*0.25/n, squaring both sides
0.0009n=1
n=1111.11 or 1112 using z=2
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using z=2.326 which is for 98% CI
0.0009=2.326^2*0.25/n
n=2.326^2*0.25/0.0009=1502.85 or 1503