This Problem Set is a part of the Lesson 9, Unit 4, Grade 7. In this lesson, students solve multi-step word problems related to percents that change. Students solve percent problems where quantities and percents change. They use a variety of methods to solve problems where quantities and percents change, including double number lines, visual models, and equations and identify the quantities that represent the part and the whole and recognize when the whole changes based on the context of a word problem.