If the required reserve ratio is 20 percent, the maximum increase in the money supply is $2,000 billion.
First step
Multiplier=1/Reserve ratio
Multiplier=1/0.20
Multiplier=5
Second step
Increase in money supply=Multiplier×Federal reserve
Increase in money supply=5×$400
Increase in money supply=$2,000 billlion
Therefore If the required reserve ratio is 20 percent, the maximum increase in the money supply is $2,000 billion.
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