Question: 1. Larry Williams made a 60-month loan that has interest of $2,518. He paid the loan in full with 21 months remaining. The interest is refunded based on the rule of 78. Find the amount of interest to be refunded.
2. A 30-month loan that has interest of $3,987 is paid in full with 7 months remaining. Find the amount of interest to be refunded using the rule of 78.