This Problem Set is a part of the Lesson 18, Unit 3, Grade 4. In this lesson, students solve two-digit by one-digit division problems that may contain remainders in the tens or the ones place. Students began solving division problems using place value disks and long division, progress to solving with only long division, and end with using mental math to solve the problems. Students use number bonds to support their mental math and are encouraged to solve division problems without that scaffold as they progress.