Answer:
112.569 ( D )
Step-by-step explanation:
Applying the estimated Regression Equation
y = b1X1 + b2X2 + a
b1 = ((SPX1Y)*(SSX2)-(SPX1X2)*(SPX2Y)) / ((SSX1)*(SSX2)-(SPX1X2)*(SPX1X2)) = 596494.5/635355.88 = 0.93884
b2 = ((SPX2Y)*(SSX1)-(SPX1X2)*(SPX1Y)) / ((SSX1)*(SSX2)-(SPX1X2)*(SPX1X2)) = 196481.5/635355.88 = 0.30925
a = MY - b1MX1 - b2MX2 = 149.25 - (0.94*61.31) - (0.31*193.88) = 31.73252
y = 0.939X1 + 0.309X2 + 31.733
For x1 ( age ) =39, and x2(weight) =143
y = (0.93884*39) + (0.30925*143) + 31.73252= 112.569
where
Sum of X1 = 981
Sum of X2 = 3102
Sum of Y = 2388
Mean X1 = 61.3125
Mean X2 = 193.875
Mean Y = 149.25
attached is the Tabular calculation of the required values needed for estimated regression equation
