> MACROECONOMICS A required reserve ratio of 5 percent yields a deposit multiplier of?

MACROECONOMICS A required reserve ratio of 5 percent yields a deposit multiplier of?

Posted at: 2014-12-05 
I know the answer is 20 but I am not sure why can someone explain?

1 / 5% = 1 / 0.05 = 20

I know the answer is 20 but I am not sure why can someone explain?