Question

A university economist conducted a study of elementary school lunch menus. During the​ state-mandated testing​ period, school lunches averaged 873 calories. The economist claimed that after the testing period​ ended, the average caloric content of the school lunches increased significantly. Set up the null and alternative hypothesis to test the​ economist's claim.

Answer 1

We are given here that during the state-mandated testing​ period, school lunches averaged 873 calories, and as we are comparing the average calories after the end of the period with this figure of 873 calories, the hypothesized mean value here is given as 873 calories.

Also, as we are testing whether the average caloric content of the school lunches increased significantly, therefore this is a one tailed test, specifically an upper tailed test. Therefore using the above 2 values, we get the null and the alternative hypothesis here as:

These are the required null and alternate hypothesis here.