SOLUTION: You want to obtain a sample to estimate how much parents spend on their kids birthday parties. Based on previous study, you believe the population standard deviation is approximate
Algebra ->
Probability-and-statistics
-> SOLUTION: You want to obtain a sample to estimate how much parents spend on their kids birthday parties. Based on previous study, you believe the population standard deviation is approximate
Log On
Question 1194708: You want to obtain a sample to estimate how much parents spend on their kids birthday parties. Based on previous study, you believe the population standard deviation is approximately σ=71.2 dollars. You would like to be 99% confident that your estimate is within 1.5 dollar(s) of average spending on the birthday parties. How many parents do you have to sample? Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! 99% CI is z(0.995)*sigma/sqrt(n)=1.5
z=2.576
so 2.576*71.2/sqrt(n)=1.5
square both sides and move the n over
33639.67=2.25 n
n=14,951
