let x be the number of tickets sold. With 548 being the max number. Since students bought 3 x the tickets, let 3x represent the number of student tickets and x be the number of adult tickets sold. That would give you an equation like this: 3x+x=548, add the like terms, you get 4x=548. Now solve for x by dividing both sides by 4, the 4's on the left cancel leaving x. Now your equation will look like this: x=548/4.