Lesson objective: Use multiplication to check division problems with remainders.

This lesson helps to build fluency with checking division problems through multiplication and addition. Picture models are used here because it supports understanding that the remainder has to be added to the multiplication problem when checking division. This work develops students' understanding that the relationship between multiplication and division holds even when the division results in a remainder. (100 / 40 = 2 R 20: therefore, 100 = 2 x 40 + 20).

Students engage in Mathematical Practice 2 (Reason abstractly and quantitatively) as they determine how to treat the remainder and check division problems.

**Key vocabulary:**

- dividend
- divisor
- inverse
- operation
- quotient
- remainder
- tallies