# Lesson 17

Apliquemos el redondeo

### Lesson Purpose

The purpose of this lesson is for students to use rounding to learn about situations and solve problems involving multi-digit whole numbers within 1 million.

### Lesson Narrative

Previously, students extended their knowledge of rounding to the nearest 1,000, 10,000, and 100,000. They began to generalize strategies for rounding any number within 1,000,000 to any place. In this lesson, students practice rounding such numbers and interpret the rounded numbers in context in order to solve problems. In doing so, they practice reasoning quantitatively and abstractly (MP2). Students also learn the benefits and limitations of rounding numbers when solving problems.

• Engagement
• MLR7

### Learning Goals

Teacher Facing

• Describe how rounding can help or hinder problem-solving.
• Round multi-digit whole numbers within 1,000,000 to solve problems.

### Student Facing

• Redondeemos números grandes para entender situaciones y resolver problemas.

Building Towards

### Lesson Timeline

 Warm-up 10 min Activity 1 20 min Activity 2 15 min Activity 3 15 min Lesson Synthesis 10 min Cool-down 5 min

### Teacher Reflection Questions

What surprised you about students’ thinking in today’s activities? What reasoning strategies did you anticipate? What did you not anticipate?

### Suggested Centers

• Mystery Number (1–4), Stage 5: Six-digit Numbers (Addressing)
• Tic Tac Round (3–5), Stage 1: Nearest Ten or Hundred (Supporting)