Question
A survey of 33 randomly selected iPhone owners showed that the purchase price has a mean...
A survey of 33 randomly selected iPhone owners showed that the purchase price has a mean of $630 with a sample standard deviation of $26.
Compute the standard error of the sample mean
Compute the 99% confidence interval for the mean.
To be 99% confident, how large a sample is needed to estimate the population mean within $11?
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