Elementary Statistics
posted by KAOS .
Compare the 95% and 99% confidence intervals for the hours of sleep a student gets. Explain the difference between these intervals and why this difference occurs.

A random sample of 50 movie patrons results in an mean IQ score of 103.0. Assuming that the population standard deviation is known to be 15, construct a 95% confidence interval estimate of the mean IQ score of all movie patrons.
Can we safely say the movie patrons have a mean IQ greater than 100?