Marsha has a 4-year student loan of $12,800. If she starts paying the loan off while attending college, she will receive a 5.5% rate compounded annually. If she waits until she graduates, her interest rate will increase to 8.1% compounded annually.

Sarah took the advertising department from her company on a round trip to meet with a potential client. including sarah a total of 11 people took the trip. she was able to purchase coach tickets for $280 and first class tickets for $1280. she used her total budget for airfare for the trip, which was $6080. how many first class tickets did she buy? how many coach tickets did she buy?