Question 23134
Is this what you mean?
He accumulated simple (not compound) interest on the loan
for two years at 7% annual rate, then he paid off
30000 of the combined pricipal and accumulated interest.
Then he accumulated  7% simple (not compound) interest for 
three years on that remaining balance and finally paid
off the entire accumulated balance?
 
If your answer to this question is , yes,  I do not see
how the answer to the question is 71700.
Cheers,
Stan H.