SOLUTION: A study of 420,098 cell phone users found that 139 of them developed cancer of the brain or nervous system. Prior to this study of cell phone​ use, the rate of such cancer was fo

Algebra ->  Probability-and-statistics -> SOLUTION: A study of 420,098 cell phone users found that 139 of them developed cancer of the brain or nervous system. Prior to this study of cell phone​ use, the rate of such cancer was fo      Log On


   

Question 1155903: A study of 420,098 cell phone users found that 139 of them developed cancer of the brain or nervous system. Prior to this study of cell phone​ use, the rate of such cancer was found to be 0.0206​% for those not using cell phones. Complete parts​ (a) and​ (b).
a. Use the sample data to construct a 95​% confidence interval estimate of the percentage of cell phone users who develop cancer of the brain or nervous system.
nothing​%less thanpless than
nothing​%
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
p hat=0.000331
half-interval is z0.975*sqrt(p(1-p)/n), p=0.000331 and 1-p=0.999669
=1.96*sqrt(0.0000331/420098)
=0.0000281*1.96=0.055 se
add and subtract from mean
(.028%, .039%)
Since 0.0206% is not in the interval can conclude there is a difference.