Answer: the answer is 90.0
Explanation:
From the question above, we are given:
G = 11
I = 4
X = M = 0
Consumption function is:
C = k + cY
Where:
k = 3
c = 0.8
The GDP of a nation is given as:
Y = C + I + G + NX
By imputing the values into the GDP equation, we have:
Y = k + cY + 4 + 11 + 0
Y = 3 + 0.8Y +15
Y - 0.8Y = 18
0.2Y = 18
Y = 90.0