In: Economics
| 
 Components  | 
 RM (million)  | 
| 
 Autonomous Consumption (Co)  | 
 55  | 
| 
 Investment (I)  | 
 165  | 
| 
 government expenditure (G)  | 
 195  | 
| 
 Personal Income Taxes (T)  | 
 255  | 
| 
 Net Export (NX)  | 
 0  | 
Using information in the table above, given the marginal propensity to consume (MPC) is 80%, find the following;
If the government increases its purchases by RM 200 million, what will be the new equilibrium real GDP? [Hint: Show your computation using multiplier
(a) Consumption function: C = Co + MPC (YD)
Where, Co is autonomous consumption. Autonomous consumption is the level of consumption at zero level of output.
YD is disposable income.
YD = Y - T
=> C = 55 + 0.8YD
consumption is measured in RM million
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(b) Saving function: S = So + MPS (YD)
So is the saving at zero level of income. It is equal to negative of autonomous consumption.
=> So = -55
MPC + MPS = 1
=> MPS = 1 - MPC
=> MPS = 1 - 0.8
=> MPS = 0.2
S = -55 + 0.2YD.
Saving is measured in RM million
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(c) TE = C + I + G + NX
=> TE = 55 + 0.8(YD) + 165 + 195 + 0
=> TE = 415 + 0.8(Y - T)
=> TE = 415 + 0.8(Y - 255)
=> TE = 415 + 0.8Y - 204
=> TE = 211 + 0.8Y
Note: TE and aggregate expenditure are same.
TE is measured in RM million
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(d) TE =AE = 211 + 0.8Y

Note: TE = aggregate expenditure
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(e) At equilirium; Y = AE
=> Y = 211 + 0.8Y
=> Y - 0.8Y = 211
=> 0.2Y = 211
=> Y = 211/0.2
=> Y = 1055
Equilirium real GDP is RM1055 million.
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(f) MPC = 0.8
Government spending multiplire = 1 / (1-MPC)
Government spending multiplire = 1/ (1 - 0.8)
Government spending multiplire = 5
Government spending increases by RM 200 million.
----------------------
Government spending multiplier = (change in real GDP / change in government spending)
=> 5 = (chnage in real GDP / RM 200 million)
=> Change in real GDP = 5 * RM 200 million
=> Change in real GDP = RM 1000 million
Hence. the real GDP will rise by RM 1000 million.