Independent solution

How to solve this Comparison of Repayment Methods question

Setup

Setup

For the level-payment option, first determine the annual payment from the 2,000 loan value and the ten-year annuity factor at 8.07%. For the equal-principal option, the outstanding balances before interest are 2,000, 1,800, …, 200.

2000=Pa100.0807P=2992000=Pa_{\overline{10}|\,0.0807}\Longrightarrow P=299

Model

Model

Total payments under the two methods are equal. The second method’s total interest is therefore i times the sum of those ten opening balances, which is 11,000.

total interest under option ii=i(2000+1800++200)\text{total interest under option ii}=i(2000+1800+\cdots+200)

Compute

Compute

The level-payment method pays 2,990 in total, so its interest is 990. Setting 11,000i = 990 gives i = 9.00%.

29902000=11000ii=0.092990-2000=11000i\Longrightarrow i=0.09

Answer

Answer

The calculation gives 9.00% for comparison of repayment methods, matching published choice B.

i=9.00%(B)\boxed{i=9.00\%\quad\text{(B)}}

Calculator reproduction

BA II Plus keystrokes

Check END/BGN, period, sign, TVM, and cash-flow setup

  1. 2nd CLR TVM; 10 N; 8.07 I/Y; 2000 +/- PV; 0 FV; CPT PMT299.00This reproduces the level-payment option before comparing total interest.