The owner of Maumee Ford-Mercury-Volvo wants to study the relationship between the age of a car and its selling price. Listed below is a random sample of 12 used cars sold at the dealership during the last year. Car 1 2 3 4 5 6 Age (years) Selling Price ($000) 9 8.1 7 6.0 11 3.6 12 4.0 8 5.0 7 10.0 Car 7 8 9 10 11 12 Age (years) Selling Price ($000) 8 7.6 11 8.0 10 8.0 12 6.0 6 8.6 6 8.0 Click here for the Excel Data File a. If we want to estimate selling price on the basis of the age of the car, which variable is the dependent variable and which is the independent variable? is the independent variable and (Click to select) is the dependent (Click to select) variable. b-1. Determine the correlation coefficient. (Negative amounts should be indicated by a minus sign. Round your answers to 3 decimal places.) X Y ( )2 ( )2 ( )( ) 9.0 8.1 1.192 0.007 1.420 0.099 7.0 6.0 -0.908 3.674 0.825 1.741 11.0 3.6 2.083 4.340 10.945 -6.892 12.0 4.0 3.083 9.507 8.458 -8.967 8.0 5.0 -0.917 -1.908 3.642 1.749 7.0 10.0 -1.917 3.092 9.558 -5.926 8.0 7.6 -0.917 0.692 0.840 -0.634 11.0 8.0 2.083 1.092 4.340 2.274 10.0 8.0 1.083 1.092 1.174 1.192 12.0 6.0 3.083 -0.908 9.507 0.825 6.0 6.0 8.6 8.0 -2.917 -2.917 1.692 1.092 8.507 8.507 2.862 1.192 107.000 82.900 -4.934 -3.184 = = sx = sy = r= b-2. Determine the coefficient of determination. (Round your answer to 3 decimal places.) c. Interpret the correlation coefficient. Does it surprise you that the correlation coefficient is negative? (Round your answer to nearest whole number.) correlation between age of car and selling price. So, % of the (Click to select) variation in the selling price is explained by the variation in the age of the car. 136____________________________________________________________________________________ The following sample observations were randomly selected. Click here for the Excel Data File X: Y: 5 13 3 15 6 7 3 12 4 13 4 11 6 9 8 5 a. Determine the regression equation. (Negative amounts should be indicated by a minus sign. Round your answers to 3 decimal places.) X ( Y 5 13 3 15 6 12 1.875 4 13 0.875 2 7 3 ) 2.375 1.875 ( ) 2 ( )( ) 5.641 3.516 8.203 13.141 4.078 1.375 0.766 2.078 4 11 6 9 8 5 = 0.375 1.125 0.141 1.625 31.641 = sx = sy = r = b = a = Y' = + b. Determine the value of X when X is 7. (Round your answer to 3 decimal places.) 17.578