Answer:
a. decrease taxes by $200 billion
Step-by-step explanation:
Given that;
Real GDP = $400 billion
Employment GDP = $800 billion
Marginal propensity to consume(MPC) = 0.5
We will apply the formula for inflationary gap and tax multiplier.
Inflationary gap = Real GDP - Full employment GDP
= ($400 billion - $800 billion)
= -$400 billion
Also,
Tax multiplier = 1 / 1 - MPC
= 1 / 1 - 0.5
= 1 / 0.5
= 2.
In the light of the above, we can say that ;
increase real GDP by $400 billion and tax should decrease by $200 billion I.e
= -$400 billion / 2
= -$200 billion
Hence, the correct option is A, decrease taxes by $200 billion.