Modern medical practice tells us not to encourage babies to become too fat. Is there a positive correlation between the weight x of a 1-year-old baby and the weight y of the mature adult (30 years old)? A random sample of medical files produced the following information for 14 females:

Complete parts (a) through (c), given ˆ‘x = 300, ˆ‘y = 1775, ˆ‘x2 = 6572, ˆ‘y2 = 226,125, and ˆ‘xy = 38,220.
(a) Draw a scatter diagram for the data.

(c) Find the sample correlation coefficient r and the coefficient of determination r2. What percentage of variation in y is explained by the least-squares model?
(d) If a female baby weighs 20 pounds at 1 year, what do you predict she will weigh at 30 years of age?

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x b) 21 25 23 24 20 15 25 2 17 24 26 22 18 19 y (lb) 125 125 120 125 130 120 145 130 130 130 130 140 110 115