Five people are on a diet reduction plan. Estimate the regression for the relationship between the number of pounds of weight lost and the number of weeks each of the five people were on the plan. These five paired observations are given below, where X represents the number of weeks on the diet and Y represents the number of pounds lost.
X: 3 2 1 4 5
Y: 6 5 4 9 11
a) Compute and graph a least-squares regression line relating weight loss to weeks on the diet.
b) Using the regression line estimate how many weeks should one diet to expect to lose 20 pounds.
c) How much variation in weight loss is explained by dieting?