Help as soon as possible

Could somebody me with this radical simplification?

Simplify 24÷(-2)(3)+7 a. -29 b. 3 c. 11

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?