math
posted by na name .
Earl Miller plans to buy a boat for $19,500 with an interest charge of $2,500. Earl figures he can afford a monthly payment of $650. If Earl has to pay 36 equal monthly payments, by how much can he afford the boat per month

since they've given the total amount of interest, just add it to the principal and divide by 36.
(19500+2500)/36 = 611.11
Looks like he has $38.89/month to spare.