The Economics of Money, Banking and Financial Markets 4th Edition by Frederic Mishkin

Exercise 13

Unless otherwise noted, the following assumptions are made in all questions: The required reserve ratio on checkable deposits iS₁0%, banks do not hold any excess reserves, and the public's holdings of currency do not change.
If you decide to hold $100 less cash than usual and therefore deposit $100 more cash in the bank, what effect will this have on checkable deposits in the banking system if the rest of the public keeps its holdings of currency constant?