Paul owes paula $.35 and has a pocket full of five cents $.10 coins and $.25 coins that he can use to pay her what is the difference between the largest in the smallest number of coins he can use to pay her

First, what is the smallest amount of coins? it would be 1, if there was a 35 cents coin, but there isn't: so it will be 2: a .25 $ and a .10 $ coin.

the maximum amount of coins is by using the smallest coins, which is 0.05$. he would use 35/5=7 coins

and the difference is 5: 7-2=5