A researcher desires to know whether the typing speed of a secretary (in words per minute) is related to the time (in hours) that it takes the secretary to learn to use a new word processing program. The data are shown.
Speed x 48 74 52 79 83 56 85 63 88 74 90 92
Time y 7 4 8 3.5 2 6 2.3 5 2.1 4.5 1.9 1.5
(a) find the values of the correlation coefficient and the coefficient of determination.
(b) find the slope, y-intercept, and equation of the regression line for the data.
(c) plot the points and a graph of the regression line on the same axes.
The solution determines the correlation and regression lines of the data.