• Let’s add and subtract within 20.

Warm-up Number Talk: Make 10

Find the value of each sum mentally.

Activity 2 Add and Subtract within 20

Find the value of each expression.

Show your thinking using drawings, numbers, or words.

Problem 1

Here are the numbers on seven cards:

• 1

• 2

• 3

• 5

• 6

• 7

• 9

1. Choose three of the numbers to add to get as close as you can to 20.

2. Write an equation to show your choice.