I can not figure out the math. I get 300 billion for both.

Suppose that every additional 3 percentage points in the investment rate boosts GDP growth by 1 percentage point. Assume also that all investment must be financed with consumer saving. Note: Investment rate = Investment/GDP The economy is currently characterized by Consumption: $8 trillion Saving (= Investment): $2 trillion GDP: $10 trillion If the goal is to raise the growth rate by 2 percentage points, a. by how much must investment increase? billion b. by how much must consumption decline? billion