Tony is offering Phil two repayment plans for a long overdue loan. Offer 1 is a visit from an enforcer and the debt is due in full at once. Offer 2 is to pay back $4,000 at the end of each year at 15% interest rate until the loan principal is paid off. Phil owes Tony $20,000. How long will it take for Phil to pay off the loan if he takes Offer 2?
