Randy, a student, has $500 to deposit in a new checking account, but Randy knows he will not be able...

Randy, a student, has $500 to deposit in a new checking account, but Randy knows he will not be able to maintain a minimum balance. He will not use an ATM card, but will write a large number of checks. Randy is trying to choose between the unlimited check writing offered by South Trust Bank and the low per check fee offered by Sun Coast Bank. How many checks would Randy have to write each month for the account at South Trust Bank to be the better option?