Maurice took out a 25-year loan from his bank for $165,000 at an APR of 2.4%, compounded monthly. If his bank charges a prepayment fee of 6 months' interest on 80% of the balance, what prepayment fee would Maurice be charged for paying off his loan 11 years early? A. $818.55 B. $740.77 C. $585.55 D. $731.94

First compute 25-11=14 years. 
Computing the yearly interest:
[tex]165,000(1+0.024)^{25}=298526[/tex]
[tex] \frac{298526}{25}=11941,04/year[/tex]
After 14 years, the amount paid by maurice s the following:
[tex]11941,04\times11=\$131351[/tex]
So there remains 
[tex]298526-131351=\$167175[/tex]
Compute 80% of \$167175:
[tex]\$167175\times0.8=\$133740[/tex]
2.4/6=0.4%
Compute 0.4% of $133740:
[tex]$133740\times0.004=\$534[/tex]

The correct answer is C.