Linda is buying boxes of ice cream sandwiches for her class party. she has to decide how many boxes she should purchase. a formula for this scenario is: z=ax/y where z=number of boxes, a= number of bars each student will eat, x= number of students at the party, y= number of ice cream bars per box. linda has 15 students in her class, and she wants each student to have 2 ice cream sandwiches. if there are 10 sandwiches in a box, how many boxes should linda buy?