To find the equation of the least squares line ÿ = a +bx.
Age Let x be age of a licensed driver in years. Let y be the percentage of all fatal accidents (for a given age) due to failure to yield the right of way. For instance, the first data pair says that 5% of all fatal accidents involving 37yearolds are due to failure to yield the right of way. The Wall Street Journal article referenced in Problem 5 reported the following data:
x

37

47

57

67

77

87

Y

5

8

10

16

30

43

(a) Sketch a scatter diagram displaying the data.
(b) Confirm the given sums Σx, Σy, Σx², Σy², Σxy and the value of the sample correlation coefficient r.
(c) Find x, y, a, and b. Then find the equation of the least squares line ÿ = a +bx.
(d) Graph the leastsquares line on your scatter diagram. Be sure to use the point (x, y) as one of the points on the line.
Complete parts (a) through (e), given Σx = 372, Σy = 112, Σx² = 24,814, Σy² = 3194, and Σxy = 8254, and r ≈ 0.943.
(f) Predict percentage of all fatal accidents due to failing to yield the right of way for 70yearolds.