If you have 90 students going on a trip and have a budget, (including a fee), of $542.94 you can subtract the fee from this total to find how much each students ticket costs. $542.94 - $45.82 = $497.12 and then divide that by 90 students to determine the ticket cost. $497.12 / 90 = $5.52333… or $5.52 per ticket.