what formula would i use to solve for this:

Question

Loan Interest A developer needs $80,000 to buy land. He is able to borrow the money at 10% per year compunded quarterly. How much will the interest amount to if he pays off the loan in 5yrs?

You need a loan amortization table to determine the quarterly installment payment required to pay off the loan in 5 years (20 quarters). You can find a useful took at http://www.yona.com/loan/
I get the quarterly payment to be $5131.77 and the total interest paid to be $22,635.40