This Application Problem is a part of the Lesson 6, Unit 3, Grade 1. Julia's lollipop is 15 centimeters long. She measured the lollipop with 9 red centimeter cubes and some blue centimeter cubes. How many blue centimeter cubes did she use? Remember to use the RDW process. This problem enables students to continue working with take apart with difference unknown problem types within the context of measurement.