SOLUTION: A population is estimated to have a standard deviation of 15. We want to estimate the population mean within 3, with a 90% level of confidence. (Use z Distribution Table.) How

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Question 1058596: A population is estimated to have a standard deviation of 15. We want to estimate the population mean within 3, with a 90% level of confidence. (Use z Distribution Table.)

How large a sample is required? (Round the z-values to 2 decimal places. Round up your answer to the next whole number.)

Sample required is .
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
The CI has to be 3.
3=z*sigma/sqrt(n);z=1.65, sd=15
3 sqrt(n)=1.65*15=24.75
sqrt (n)=8.25
n=68.06, rounds up to 69.