Question

In a plant that fills 12 ounce cans of soda, the mean fill amount with the current machinery is 12.2 ounces with a standard deviation of 0.03 ounces. A new machine is said to be more accurate, so the company tested this new machine on a run of 10 cans, and obtained the following fill amounts:

12.03 12.10 12.02 11.92 12.10

12.00 12.05 11.97 11.99 11.87

Test the claim that the standard deviation of the new machine is lower than the standard deviation of the original machine at a 1% significance level, because purchasing the new machines is very expensive.

The alternative hypothesis is :  

The distribution is

The critical value(s) is/are:  

The test value is

We (choose reject/fail to reject)   the null hypothesis

We (choose do/do not)   recommend purchasing the new machines.

Answer 1