The 24 students in ms. lees class each collected an average of 18 cans for recycling. then 21 students in mr. galvez's class each collected an average of 25 cans for recycling. how many more cans were collected by mr. galvez's class than ms. lee's class

This can be solve by using the average cans of each student collected and muliply it by the total students. Since for ms. Lee has 24 students and each student collected 18 cans on average, so the total can her class collected on average is 432 cans. For mr galveshas 21 students and collected 25 can per syudents on average, so the total is 525 cans. So 525 - 432 = 93 more cans the class of mr galvez collected