Macroeconomics 5th Edition by Olivier Blanchard

Exercise 8

The money multiplier
The money multiplier is described in Section 4-4. Assume the following:
i. The public holds no currency.
ii. The ratio of reserves to deposits is 0.1.
iii. The demand for money is given by
M d = $Y (.8 - 4i )
Initially, the monetary base is $100 billion, and nominal income is $5 trillion.
a. What is the demand for central bank money
b. Find the equilibrium interest rate by setting the demand for central bank money equal to the supply of central bank money.
c. What is the overall supply of money Is it equal to the overall demand for money at the interest rate you found in part (b)
d. What is the impact on the interest rate if central bank money is increased to $300 billion
e. If the overall money supply increases to $3,000 billion, what will be the impact on i [Hint: Use what you discovered in part (c).]