My auto insurance can be paid in installments. If paid annually, it costs $450. If paid in installments, 40% is paid at month 0, and 15% at the ends of months 2, 4, 6, and 8. A delayed payment plan fee of $10 is added to all 5 installment payments. If the installment plan is chosen, what is the effective annual interest rate being paid on the "loan"? (Answer: 53.7%)