The equation to predict GPA (range 0-4.0) is y=.21+.51x1+.0022, where x1 is high school GPA (range 1-4.0) and x2 is college board score (range 200-800). Use the multiple regression equation to predict college GPA for high school GPA of 3.5 and college board score of 400. The predicted college GPA for a high school GPA of 3.5 and a college board score of 400 is ? Solution Plug in the numbers. y = 0.21 + 0.51(3.5) + (0.002)(400) = 2.795.