Question

Consider an economy described by the following equations:

Y = C + I + G + NX,

Y = 5,000,

G = 1,000,

T = 1,000,

C = 250 + 0.75(Y – T),

I = 1,000 – 50r,

NX = 500 – 500e,

r = r* = 5.

a. In this economy, solve for national saving, investment, the trade balance, and the Equilibrium exchange rate.

b. Suppose now that G rises to 1,250. Solve for national saving, investment, the trade balance, and the equilibrium exchange rate. Explain what you find.

Answer 1

a. exchange rate = 1

b. exchange rate = 1.5

Step-by-step explanation:

(a) National Saving = Private saving + public saving

Private saving = Y - C - T

=> Private saving = 5000 - (250 + 0.75(Y – T)) - 1000

=> Private saving = 5000 - (250 + 0.75(5000 – 1000)) - 1000 = 750

Public saving = T - G = 1000 - 1000 = 0

National saving = 750 + 0

= 750

Investment = 1000 - 50r = 1000 - 50*5

= 750

Y = C + I + G + NX

Trade Balance = Y - C - G - I = 5000 - (250 + 0.75(5000 – 1000)) - 1000 - 750 = 0

Thus Trade Balance = 0

NX = 0 => NX = 500 – 500e = 0

=> e = 1

Thus exchange rate = 1

(b)

National Saving = Private saving + public saving

Private saving = Y - C - T

=> Private saving = 5000 - (250 + 0.75(Y – T)) - 1000

=> Private saving = 5000 - (250 + 0.75(5000 – 1000)) - 1000 = 750

Public saving = T - G = 1000 - 1250 = -250

National saving = 750 - 250

= 500

Investment = 1000 - 50r = 1000 - 50*5

= 750

Y = C + I + G + NX

Trade Balance = Y - C - G - I = 5000 - (250 + 0.75(5000 – 1000)) - 1250 - 750 = -250

Thus Trade Balance = -250

NX = -250 => NX = 500 – 500e = -250

=> e = 750/500 = 1.5

Thus exchange rate = 1.5