A school offered its students an optional field trip. If 15 or fewer students went on the field trip, the charge for each student would be $11.50. If more than 15 students chose to go on the field trip, the charge for each student would be $10.25. 18 students opted to go on the tour, but each pre-paid $11,50. The students agreed to put the extra amount toward dinner on the trip. How much total money will be put toward dinner on the trip?​