A retired couple buys a new recreational vehicle (RV) for $42,000.00. They make a down payment of

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Question:

A retired couple buys a new recreational vehicle (RV) for $42,000.00.
They make a down payment of $13,000.00 and finance the balance at 9.0% APR over 60 months.
Their monthly payment is $601.99.
Instead of making the 12th payment, the couple decides to pay the remaining balance on the loan.
Use the actuarial method to determine how much interest the couple will save.

the result will match exactly with one of the answers. If you use a spreadsheet to do the computation, your result will not match exactly with any of the answers, but it will differ only very little (mostly less than $1) from the "correct" answer.