07 CE MC Q.36

Here is the situation of a banking system:

Assets:
-reserve $250
-loans $750

Liabilities:
deposit $1000

Required Reserve ratio is 20%.If $100 is withdrawn from the banking system,what is the maximum possible total deposits?

I want to ask if my method is correct(mine is not same as the solution's):
Deposit contraction = $100/20% = $500
So maximum deposit = 1000-500 = $500

So maximum TOTAL deposit = 500+reserve = 500+250 =$750