Answer: D. 25%
Explanation:
Here the present value, PV = $320 - $ 100 = $ 220
Total number of period, n = 12
And, Payment per month, P = $25
Therefore, the amount he paid in 12 months = 25×12 = 300
Thus, the extra amount he paid = 300 - 220 = $80
So, the more amount he paid than the actual amount =
Thus, she paid 25 % extra.