A new weight-reducing technique, consisting of a liquid protein diet, is currently undergoing tests by the Food and Drug Administration (FDA) before its introduction into the market. The weights of a random sample of five people are recorded before they are introduced to the liquid protein diet. The five individuals are then instructed to follow the liquid protein diet for 3 weeks. At the end of this period, their weights (in pounds) are again recorded. The results are listed in the table.

Person Weight Before Diet Weight After Diet

1 167 160

2 212 207

3 205 202

4 214 208

5 221 217

Total 1019 994

Is there a significant difference between the means of the weights before and after the diet? Use = 0.01