# Lesson 10 Tens and Tens, Ones and Ones

Let’s add two-digit numbers.

## Warm-up How Many Do You See: Tens and Ones

How many do you see?

How do you see them?

## Activity 1 Priya‘s Work

Find the value of

Priya’s work

How did Priya find the value?

## Activity 2 Finish the Work

## Problem 1

Each expression shows a first step to find the number that makes each equation true.

Finish the work to find the number that makes each equation true.

Show your thinking using drawings, numbers, or words.

First step:

First step:

## Problem 2

Find the value of each sum.

Show your thinking using drawings, numbers, or words.

## Activity 3 Introduce Number Puzzles: Within 100 with Composing

These number puzzles have addition equations with two-digit numbers. Use the digit cards to make each equation true. Remember that you can only use each card once on a page.

## Practice Problem

## Problem 1

Find the value of

.

Show your thinking using drawings, numbers, or words.Can you find the value in a different way?