How is the n if the original number is more than 1?

For a field trip to the zoo, 4 students rode in cars and the rest filled nine busess. how many students were in each bus if 472 students were on the trip

Ineed i been stuck on this question since yesterday

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?