The following table presents the ages of the last 10 U.S. presidents and their wives on the first day of their presidencies.

a. Compute the least-squares regression line for predicting the president’s age from the first lady’s age.

b. Compute the coefficient of determination.

c. Construct a scatterplot of the presidents’ ages (y) versus the first ladies’ ages (x).

d. Which point is an outlier?

e. Remove the outlier and compute the least-squares regression line for predicting the president’s age from the first lady’s age.

f. Is the outlier influential? Explain.
g. Compute the coefficient of determination for the data set with the outlier removed. Is the proportion of variation explained by the least-squares regression line greater, less, or about the same without the outlier?
Explain.

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Name Donald and Melania Trump Her Age His Age 46 70 Barack and Michelle Obama 45 47 George W. and Laura Bush 54 54 Bill and Hillary Clinton 45 46 George and Barbara Bush 55 64 Ronald and Nancy Reagan 59 69 Jimmy and Rosalynn Carter 49 52 Gerald and Betty Ford 56 61 Richard and Pat Nixon 56 56 Lyndon and Lady Bird Johnson 50 55