A design on a balloon is 8 centimeters wide when the balloon holds 25 cubic centimeters of air . How much air must the balloon hold for the design to be 16 centimeters wide.

What expression is equivalent to 1/2(2+3x-6)

Icould really use some with this question.

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?