5.40 The effect of changing units. The equation of a regression line, unlike the correla- tion, depends on the units we use to measure the explanatory and response variables. Here are data on knee height and overall height (in centimeters) for five elderly men: Knee height x Height y 57.7 192.1 55.2 47.4 43.5 44.8 146.4 162.7 169.1 153.3 (a) Find the equation of the regression line for predicting overall height in cen- timeters from knee height in centimeters. (b) A mad scientist decides to measure knee height in millimeters and height in meters. The same data in these units are Knee height x Height y 577 474 1.921 1.533 435 1.464 448 1.627 552 1.691 Find the equation of the regression line for predicting overall height in meters from knee height in millimeters. (c) Use both lines to predict the overall height of a man whose knee height is 50 centimeters, which is the same as 500 millimeters. Use the fact that there are 100 centimeters in a meter to show that the two predictions are the same (up to roundoff error). regression lines for predicting FPG