Question

Use the traditional method to test the given hypothesis. Assume that the population is normally distributed and that the
sample has been randomly selected.
22) A machine dispenses a liquid drug into bottles in such a way that the standard deviation of
the contents is 81 milliliters. A new machine is tested on a sample of 24 containers and the
standard deviation for this sample group is found to be 26 milliliters. At the 0.05 level of
significance, test the claim that the amounts dispensed by the new machine have a smaller
standard deviation.

Answer 1

To find critical value we used chi square table.

Since, 2.37<13.09, we reject the null hypothesis at 5% level of significance.

Therefore we have enough evidence to support the claim that the amounts dispensed by the new machine have a smaller standard deviation.