The lowest rate of interest at which money is being borrowed
Not 100% sure this is right but
60cm^2
The two diagonals intersects at right-angle for a kite
the long diagonal also bisects the short diagonal so QP = PS = QS/2 = 6/2 = 3
QPR is a right-angle triangle with QR at 5 and QR at 3
RP = sqrt (5^2 - 3^) = 4m
This sort of problem is most easily worked using a financial calcualtor or app. Attached is the result of using the financial app available on a TI-84 calculator for finding future value. The arguments to the function are ...
... N — number of payments: 3
... I — annual interest rate (%): 4.95
... PV — present value: the value of the loan, 125,600
... PMT — payment amount: -1500. The sign is negative because this is money we're paying out
... P/Y — payments per year: 12 (payment is monthly)
... C/Y — compounding per year: 12 (interest is compounded monthly)
After 3 payments, the balance is $122,642.13.