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 3500 hours. You test 16 light bulbs and get the following life spans.
47,761 , 39,064 , 28,454 , 37,943 , 30,304 , 40,134 , 39,386 , 37,027, 24,412 , 33,008 , 34,674 , 35,120, 32,168 , 36,260, 35,527 , 45,268
A. find the mean of your sample (...)
B. find the standard deviation of your sample (...)