EC-312 Macroeconomic Theory
DUE Oct 14 in class
1. [20 points] State whether the statement is true or false. Provide brief explanation. If statement is
false, provide correct statement.
a. [10 points] Goods market is in equilibrium when consumption is equal income.
b. [10 points] Interest rate falls when the Central Bank sells bonds
2. [35 points] Suppose the United States economy is represented by the following equations:
Z = C + I + G C = 500 + .5YD T = 600 I = 300
YD = Y – T G = 2000
a. [10 points] Given the above variables, calculate the equilibrium level of output. Hint: First
specify (using the above numbers) the demand equation (Z) for this economy. Second, using
the equilibrium condition, equate this expression with Y. Once you have done this, solve for
the equilibrium level of output. Using the ZZ-Y graph (i.e., a graph that includes the ZZ line
and 45-degree line with Z on the vertical axis, and Y on the horizontal axis), illustrate the
equilibrium level of output for this economy.
b. [10 points] Now, assume that consumer confidence decreases causing a reduction in
autonomous consumption (c0) from 500 to 400. What is the new equilibrium level of
output? How much does income change as a result of this event? What is the multiplier for
c. [5 points] Graphically illustrate the effects of this change in autonomous consumption on
the demand line (ZZ) and Y. Clearly indicate in your graph the initial and final equilibrium
levels of output.
d. [10 points] Briefly explain why this reduction in output is greater than (in absolute terms)
the initial reduction in autonomous consumption.
3. [10 points] Graphically illustrate and explain what effect a purchase of bonds by the Federal
Reserve will have on the money market.
4. [10 points] Explain in detail what effect a Fed sale of bonds will have on: (1) the LM curve; and (2)
5. [10 points] Explain in detail what effect a reduction in government spending will have on: (1) the
LM curve; and (2) the IS curve.
6. [5 points] Which of the following about IS relation is NOT correct? A) It is the the relation between interest rate and savings.
B) It is the equilibrium condition for the goods market.
C) It stands for “Investment equals saving.”
D) It shows what firms want to invest must be equal to what people and the government wants to
7. [5 points] An open market sale of securities will tend to cause
A) a reduction in the supply of central bank money.
B) a reduction in the demand for currency.
C) a reduction in the demand for reserves.
D) none of the above
8. [5 points] Suppose there is an increase in consumer confidence. Which of the following represents
the complete list of variables that must increase in response to this increase in consumer
B) consumption and investment
C) consumption, investment and output
D) consumption and output
E) consumption, output and the interest rate