Colin buys a new car worth $25,000. He pays a 10% deposit (i.e $2500) and agrees to pay $500 at the end of each month for as long as necessary.

If interest is at 14% pa effective, find:

1. the number of payments of $500 requires

2. the amount of the final smaller payment required one month after the last full payment of $500

3. the loan outstanding after 2 years using both the retrospective and prospective methods

please see the attached working out for part 1, the answer is 62 but i am confused on how to get to that.