# Fractions / Dividing a Fraction by a Fraction

Grade Level 5,6
Activity 13 of 15
This lesson can be used to develop an understanding of dividing a fraction (a/b) by the fraction (c/d).

## Planning and Resources

Objectives
Students understand how to identify and interpret problems involving division of fractions, in particular that division of a by b can be thought of a’s the number of b’s contained in a. They use the relationship between multiplication and division to explain that a division problem can be rewritten as a multiplication problem.

Vocabulary
identity element of multiplication

Standard:

## Lesson Snapshot

#### Understanding

While the number lines are used as a tool for understanding the concept of dividing a fraction by a fraction, th goal is to enable students to be able to do so without the support of the number lines.

### What to look for

Ask students how the number lines are connected to their thinking about division of fractions and the role of equivalent fractions in the process. This can lead to a productive discussion about the mathematical concepts.

### Sample Assessment

How many (3/4)-cup servings are in (9/2) cups of yogurt?

Answer: 6 cups

#### The Big Idea

One way to think about a divided by b is to think about how many b’s are contained in a.

### What are the students doing?

Students use number lines to investigate division of fractions with numbers less than or equal to 1.

### What is the teacher doing?

Remind students that they can use multiplication to check the answers of their division problems.