This optional lesson offers students additional practice in finding the amount in one group given the amount in a different number of groups. It also prompts students to interpret, represent, and solve different kinds of division problems. In one activity, students are not explicitly told whether the situations involve finding the number of groups or finding the amount in each group. They decide on an interpretation that would enable them to solve the problem. Students are also required to identify relevant information (from a video, a picture, or written statements) that would help them answer questions. In an optional activity, they invent a situation that can be represented by a given division expression.

Because the problems in this lesson are less straightforward, students will need to make sense of the problems and persevere to solve them (MP1). As students move back and forth between the contexts and the abstract equations and diagrams that represent them, they reason abstractly and quantitatively (MP2).