You work for a consumer watchdog publication and are testing the advertising claims of a light bulb manufacturer. The manufacturer claims that the life span of the bulb is normally distributed, with a mean of 40,000 hours and standard deviation of 5,000 hours. You test 16 light bulbs and get the following life spans.
48,740 , 41,972 , 23,689 , 33,676 , 32,702 , 41,906 , 41,635 , 35,293, 23,621 , 30,265 , 34,810 , 36,564, 29,674 , 34,350 , 37,016 , 46,905
A. find the mean of your sample (...)
B. find the standard deviation of your sample (...)