Answer:
- 0.7% monthly
- 240 payments for payoff
- monthly payment $1378.41
- 120 payments in 10 years
- balance $111,655.24 after 10 years
Explanation:
For a 20-year loan of $160,000 at 8.4%, you want to know the number of payments after 10 years and for payoff, the monthly interest rate, the monthly payment, and the remaining balance after 10 years.
Part I
The periodic interest rate applied to monthly payments is the annual rate divided by the number of months in a year.
periodic rate = 8.4%/12
periodic rate = 0.7%
Part II
The number of monthly payments made on a 20-year loan is the number of months in 20 years:
months = (20 yr)×(12 mo/yr) = 240 mo
Patti will have made 240 payments to pay off the loan.
Part III
Patti's monthly payment can be found using the amortization formula.
A = Pr/(1 -(1+r)^-n) . . . . Principal P, periodic rate r, n periods
A = 160000(0.007)/(1 -1.007^-240) ≈ 1378.41
Patti's monthly payment will be $1378.41.
Part IV
The number of monthly payments in 10 years is ...
months = (10 yr)×(12 mo/yr) = 120 mo
Patti will have made 120 payments after 10 years.
Part V
The remaining balance can be found using a future value formula.
FV = P((1+r)^n -((1+r)^n -1)/(1 -(1+r)^-N))
where P is the principal value, r is the periodic rate, n is the number of payments made, and N is the number of payments used to compute the payment amount.
Here, we have P=160,000, n=120, N=240, r=0.007, so the remaining balance is computed to be ...
FV = 160000(1.007^120 -(1.007^120 -1)/(1 -1.007^-240)) ≈ 111,655.77
The amount calculated in the attachment is slightly lower, because we used the actual payment amount. That amount is rounded up from the value computed by the amortization formula, so the loan is paid off very slightly faster than the FV formula shows.
The remaining balance is about $111,655.24.
__
Additional comment
These calculations are most easily done using a financial calculator or spreadsheet. Results are most accurate when you compute the actual amortization schedule, with interest charges and payment values rounded to cents each month.
The final payment is almost always different from that calculated using a formula. The rounding of intermediate values affects the actual payoff rate, which may be more or less than the rate using high-precision values.
Here, the payment is rounded up, so the loan is paid faster, and the final payment will be less than the usual monthly payment.