# Lesson 12

Represent Division of Unit Fractions by Whole Numbers

### Lesson Purpose

### Lesson Narrative

In the previous lesson, students solved problems about dividing a unit fraction by a whole number in a way that made sense to them. In this lesson, students use tape diagrams to represent division of a unit fraction by a whole number. The tape diagrams used to represent the problems are familiar to students from earlier grades. Here is a tape diagram showing \(\frac{1}{4}\), one out of 4 pieces is shaded:

One way to show \(\frac{1}{4} \div 3\) is to divide the \(\frac{1}{4}\) into 3 equal pieces.

To see how much is shaded we can divide all of the \(\frac{1}{4}\)s and see that \(\frac{1}{4} \div 3 = \frac{1}{12}\).

Students use these diagrams to understand this series of steps representing division of a unit fraction by a whole number throughout the lesson.

- Engagement

Activity 2: Priya’s Work

### Learning Goals

Teacher Facing

- Make sense of diagrams that represent division of a unit fraction by a whole number.

### Student Facing

- Let’s make sense of diagrams that represent division of a unit fraction by a whole number.

### Required Preparation

### CCSS Standards

Addressing

### Lesson Timeline

Warm-up | 10 min |

Activity 1 | 10 min |

Activity 2 | 10 min |

Activity 3 | 15 min |

Lesson Synthesis | 10 min |

Cool-down | 5 min |

### Teacher Reflection Questions

### Suggested Centers

- Rolling for Fractions (3–5), Stage 4: Multiply Fractions (Addressing)
- Compare (1–5), Stage 4: Divide within 100 (Supporting)
- How Close? (1–5), Stage 7: Multiply Fractions and Whole Numbers to 5 (Supporting)