If on receiving a checking deposit of $300 a bank's excess reserves increased by $255, the required reserve ratio must be 15%.
The required reserve ratio is the fraction of deposits that the Federal Reserve requires banks to hold as reserves.
The reserve ratio can be computed by dividing the difference between the deposit and the increase in excess reserves by the original deposit and multiplying by 100.
Checking deposit = $300
Increase in excess reserves = $255
Required reserve = $45 ($300 - $255)
Reserve ratio = 15% ($45/$300 x 100)
Thus, if on receiving a checking deposit of $300 a bank's excess reserves increased by $255, the required reserve ratio must be 15%.
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