I understand a and b. It is C-E that I am confused about.

xy34%

x17273747576777y342420121075

xyx2y2xyr

(a) Draw a scatter diagram displaying the data.

Flash Player version 10 or higher is required for this question. 

You can get Flash Player free from Adobe’s website.

(b) Verify the given sums Σx, Σy, Σx2, Σy2, Σxy and the value of the sample correlation coefficient r. (Round your value for r to three decimal places.)Σx=Σy=Σx2=Σy2=Σxy=r=

(c) Find x, and y. Then find the equation of the least-squares line  = a + bx. (Round your answers for x and y to two decimal places. Round your answers for a and b to three decimal places.)x= y= = +  x

(d) Graph the least-squares line. Be sure to plot the point (x, y) as a point on the line.

(e) Find the value of the coefficient of determination r2. What percentage of the variation in y can be explained by the corresponding variation in x and the least-squares line? What percentage is unexplained? (Round your answer for r2 to three decimal places. Round your answers for the percentages to one decimal place.)r2 =explained     %unexplained     %

(f) Predict the percentage of all fatal accidents due to speeding for 55-year-olds. (Round your answer to two decimal places.)

 %