SOLUTION: You want to obtain a sample to estimate a population mean. Based on previous evidence, you believe the population standard deviation is approximately σ=46.2. You would like to

Algebra ->  Customizable Word Problem Solvers  -> Misc -> SOLUTION: You want to obtain a sample to estimate a population mean. Based on previous evidence, you believe the population standard deviation is approximately σ=46.2. You would like to      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 1100116: You want to obtain a sample to estimate a population mean. Based on previous evidence, you believe the population standard deviation is approximately σ=46.2. You would like to be 90% confident that your estimate is within 3 of the true population mean. How large of a sample size is required?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
90% CI half interval is 1.645+/-sigma/sqrt(n)
3=1.645*46.2/sqrt(n)
square both sides
9=5775.85/n
n=641.76 or 642