The weights of 9 of managers at Company X are determined. They have a mean of 70.2 Kg, and a standard deviation of 1.5 Kg. Use a 0.01 significance level to test the claim that managers at Company X have weights with a mean that is greater than the mean of 63.6 Kg for managers from the general population. Given that there are only nine weights represented, can we really conclude that managers at Company X are heavier than the typical managers?
Solution. We can use t-test to test the following hypotheses.
Null hypothesis H0: mu=63.6
Alternative hypothesis H1: mu>63.6
The solution does hypothesis testing for one population mean.