Lesson objective: Multiply a non-unit fraction by a whole number.

This lesson helps to build fluency with multiplying a non-unit fraction by a whole number. The previous lesson used number lines to model this same skill. In this lesson area models are used to model this skill. This work develops students' understanding that a multiple of *\(\frac ab\)* is a multiple of \(\frac1b\): n x \(\frac ab\) = \(\frac {n\ \times\ a}b\).

Students engage in Mathematical Practice 8 (look for and express regularity in repeated reasoning) as they come to recognize that multiplying the numerator by the whole number is a more efficient way to calculate repeated addition of a non-unit fraction.

**Key vocabulary:**

- multiple
- non-unit fraction
- unit fraction
- whole number

**Special materials needed:**

- access to a way to keep track of time (e.g. stop watch or easily visible wall clock with a second hand)
- game cards for "Speed" (see "Additional materials")