According to the Journal of Family Medicine Practice, high sodium intake may be related to ulcers, stomach cancer, and migraine headaches. The human requirement for salt is only 200 milligrams per day, which is surpassed in most single servings of ready-to-eat cereals.

Self Magazine performed a study regarding one of the most common ready-to-eat cereals: Special K. The main rational to perform the study is the effect in the health of many people that are carrying out the Special K Diet: 2 cups of cereal (breakfast and dinner) and 1 small meal (lunch).

A random sample of 20 similar servings of Special K Cereal has a mean sodium content of 193 milligrams of sodium and a standard deviation of 10.5 milligrams.

1. Does this suggest at the 0.05 level of significance that the average sodium content for single servings of Special K Cereal is less than 200 milligrams?