# Lesson 6 Use a Ten to Add Within 1,000

• Let’s add three-digit numbers by composing a ten.

## Warm-up Number Talk: Numbers that Make 10

Find the value of each expression mentally.

## Activity 1 Add Two-digit and Three-digit Numbers

1. Find the value of each sum.

Set 1

Set 2

Set 3

2. What patterns did you notice?

## Activity 2 Card Sort: Perfect Ten

1. Match each three-digit number to a two-digit number. When you add your numbers together they should make a ten with no extra ones.

2. Pick 1 pair of numbers and find the value of their sum. Show your thinking.

## Problem 1

Find the value of each sum. Show your thinking.