My calculations below are not included on the list of possible answers.

John borrowed money from Stan. He has to pay Stan R500 three months from now and R930 five months from now. Stan charges him an interest rate of 20% per annum, compounded monthly.

John decides to pay Stan back what he owes him two months from now. How much interest will he save?

[1] $1376.81

[2] $430.00

[3] $53.19

[4] $97.96

My calculation:

Thus the interest saved is . But this seems to be incorrect and I can't find what I'm doing wrong. Please could someone assist me?