# Lesson 17

Use the Four Operations to Solve Problems

### Lesson Purpose

The purpose of this lesson is for students to solve two-step problems using all four operations.

### Lesson Narrative

Previously, students have solved two-step problems involving addition, subtraction, and multiplication. Here they consider what mathematical questions could be asked about a situation and then solve two-step problems that include division where the factors are limited to single-digit numbers. Parentheses are revisited as a tool students can use to specify which operation happens first in the equation so that it matches the situation they are representing.

• Engagement
• MLR5

### Learning Goals

Teacher Facing

• Represent two-step word problems using equations with a letter standing for the unknown quantity.
• Solve two-step word problems using the four operations.

### Student Facing

• Let’s use the four operations to solve problems.

### Required Materials

Materials to Gather

Materials to Copy

• Centimeter Grid Paper - Standard

### Lesson Timeline

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

### Teacher Reflection Questions

How has your students’ understanding of two-step word problems evolved from previous lessons? How have their experiences with multiplication and division in this unit influenced their problem solving strategies?

### Suggested Centers

• Compare (1–5), Stage 3: Multiply within 100 (Addressing)
• How Close? (1–5), Stage 5: Multiply to 100 (Addressing)