Students learn that a combination is an arrangement of objects in which the order is not important. For example, the combination AB is the same as the combination BA. Students are then asked to solve word problems involving combinations. For example: How many different ways can 2 representatives be chosen from 4 candidates? First label the 4 different candidates as A, B, C, and D. Next, list all the different combinations of 2 representatives: AB, AC, AD, BC, BD, and CD. So there are 6 different ways that 2 representatives can be chosen from 4 candidates.