SOLUTION: a) How many weeks of data must be randomly sampled to estimate the mean weekly sales of a new line of athletic footwear? We want 95% confidence that the sample mean is within $400

Question 1156812: a) How many weeks of data must be randomly sampled to estimate the mean weekly sales of a new line of athletic footwear? We want 95% confidence that the sample mean is within $400 of the population mean, and the population standard deviation is known to be $1400.
b) Write an interpretation. (Write answer on paper)

Answer by Boreal(15235) (Show Source): You can put this solution on YOUR website!
half-interval here its z(0.975)*sigma/sqrtI(n)
400=1.96*1400/sqrt(n)
400 sqrt(n)=2744
sqrt(n)=6.86
n=47.06 or 48 weeks

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