In this situation, the money multiplier is 10. This is true no matter how much or how little is deposited in the bank. So long as the bank only keeps the amount of reserves that it is required to keep, the money multiplier will be 10.
The idea behind the money multiplier is that the bank takes in deposits, holds required reserves, and loans out the rest. This process is repeated a number of times, allowing the banking system to add much more to the money supply than the original deposit. To calculate the multiplier, though, we must assume that the bank is not keeping any excess reserves.
If the bank does not keep any excess reserves, the formula for the money multiplier is
Money multiplier = 1/required reserve ratio
In this case, that becomes
Money multiplier = 1/.10 = 10
Therefore, the multiplier in this case is 10.