Answer:
To calculate the percentage of the amount borrowed that has been repaid by the time the thirteenth payment is made, we need to first determine the total amount borrowed and then calculate the amount repaid after making twelve payments.Given that there are forty monthly payments of $200 apiece, the total amount borrowed can be calculated by multiplying the monthly payment by the number of payments:Total amount borrowed = Monthly payment * Number of paymentsTotal amount borrowed = $200 * 40Total amount borrowed = $8,000To calculate the amount repaid after twelve payments, we can use the formula for the future value of an ordinary annuity:Amount Repaid = Monthly payment * ((1 - (1 + interest rate)^-number of payments) / interest rate)Amount Repaid = $200 * ((1 - (1 + 0.12)^-12) / 0.12)Now we can calculate the percentage of the amount borrowed that has been repaid by dividing the amount repaid by the total amount borrowed and multiplying by 100:Percentage repaid = (Amount Repaid / Total amount borrowed) * 100Please note that the calculations may differ slightly based on rounding, but the following is a general estimation:Percentage repaid ≈ (Amount Repaid / Total amount borrowed) * 100By evaluating the expression, we can determine the percentage of the amount borrowed that has been repaid by the time the thirteenth payment is made.