Total cholesterol in children aged 1015 is assumed to follow

Total cholesterol in children aged 10-15 is assumed to follow a normal distribution with a mean of 191 and a standard deviation of 22.4.

What is the distribution of the mean cholesterol level in a sample of size 20?

Solution

distribution of the mean cholesterol : normal

mean of sample of size 20 : 191

SD of sample of size 20 : 22.4 / srqt(20) = 5.01