This Problem Set is a part of the Lesson 22, Unit 4, Grade 5. In this lesson, students begin extending their understanding of multiplication to include scaling. They reason about the size of products when quantities are multiplied by 1, by numbers larger than 1, and numbers smaller than 1. For example, 4/4 x 12 inches is the same length, while 3/4 x 12 inches is a shorter length, and 5/4 x 12 inches is a longer length.