Question

The total interest paid on a 3​-year loan at 9​% interest compounded monthly is ​$1505.82 determine the monthly payment for the loan.

Answer 1

Number of compounding periods is
n=12months×3years=36
I assume that

The total interest=
monthly payment×number of compounding periods - the amount of the present value of an annuity ordinary
I=x×n-pv

Let monthly payment be X

I =Total interest is 1505.82

The present value of an annuity ordinary is
Pv=X [(1-(1+0.09/12)^(-36))÷(0.09/12)]

now plug those in the formula of the total interest above
I=x×n-pv
1505.72=36X-X [(1-(1+0.09/12)^(-36))÷(0.09/12)]
Solve for X using Google calculator to get the monthly payment which is
X=330.72

Check your answer using the interest formula
36×330.72−330.72×((1−(1+0.09
÷12)^(−12×3))÷(0.09÷12))
=1,505.83