
Larry C. answered 11/19/18
Computer Science and Mathematics professional
Assuming (as is usually the case) that monthly interest (36%/12 or 3%) is calculated before payments, then:
First month's balance including interest = 1.03*850 = 875.50
10% of that (the minimum payment) would be 87.55, leaving a balance of 787.95.
Simply repeat the above steps to figure the 2nd payment (fractions usually round up when dealing with loans.)