Abdul's seventh grade class is going on a field trip to a history museum. There are x students and y teachers going on the trip. Tickets for students are $10 each and tickets for teachers are $20 each. The history museum gave the class 20% off as part of a group promotion.
Pick all the expressions that represent the total cost of the field trip.
1) (x * 10 + y * 20) - 20%
2) (x + y) * (10 - 20%)
3) x * (10 - 20%) + y * (20 - 20%)
4) (x - 20%) * 10 + (y - 20%) * 20
5) (x * 10 + y * 20) * (1 - 20%)