Q. If i gave a school 50 cents more than I owed but they didn’t know how much i owed, is it a problem?I did it for convenience ($10 bill as opposed to $9.50).

A. Horav Shlomo Miller’s Shlit”a opinion is that regardless of why you owe the $9.50 to the school, you can give them back the ten-dollar bill. The reason being that even if a ribbis prohibition applies, it would only be rabbinical, and donating the 50 cents is a permissible tzedaka contribution.

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit’a