Changes in equilibrium GDP caused by government

Question

Refer to columns 1 and columns 6 of the tabular data described below. Suppose that all taxes are personal taxes and that government spending does not induce a shift in the private aggregate expenditures schedule. Calculate and describe the changes in equilibrium GDP caused by the addition of government.

 

Answer 1

The addition of $20 billion of government expenditures and $20 billion of personal taxes raise equilibrium GDP from $350 to $370 billion. The $20 billion rise in G raises equilibrium GDP through $100 billion (= $20 billion x the multiplier of 5); the $20 billion rise in T drop consumption by $16 billion at every level. (= $20 billion x the MPC of .8). This $16 billion decline in turn decreases equilibrium GDP by $80 billion ($16 billion x multiplier of 5).  The overall change from comprising balanced government spending and taxes is $20 billion (= $100 billion - $80 billion).