Do heavier cars really use more gasoline? Suppose a car ischosen at random. Let x be the weight of the car (inhundreds of pounds), and let y be the miles per gallon(mpg).

x	25	46	33	47	23	40	34	52
y	33	22	23	13	29	17	21	14

Complete parts (a) through (e), given Σx = 300,Σy = 172, Σx² = 12,028,Σy² = 4038, Σxy = 5996, and

r ≈ −0.883.

(a) Draw a scatter diagram displaying the data.

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

Σx =	2
Σy =	3
Σx2 =	4
Σy2 =	5
Σxy =	6
r =	7

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

x	= 8
y	= 9
	= 10	+ 11 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 determinationr². What percentage of the variation iny can be explained by the corresponding variationin x and the least-squares line? What percentage isunexplained? (Round your answer for r²to three decimal places. Round your answers for the percentages toone decimal place.)

r2 =	13
explained   Â	14 %
unexplained   Â	15 %

(f) Suppose a car weighs x = 41 (hundred pounds). Whatdoes the least-squares line forecast for y = miles pergallon? (Round your answer to two decimal places.)
16 mpg