Lesson 4 Add and Subtract Your Way

- Let’s add and subtract within 30.

Warm-up Number Talk: Make 10

Find the value of each sum mentally.

$8 + 2$
$8 + 3$
$8 + 5$
$7 + 6$

Activity 1 Revisit How Close?

Digit card. Number 5.

Digit card. Number 8.

Digit card. Number 2.

Digit card. Number 4.

Digit card. Number 6.

Activity 2 Add and Subtract within 20

Find the value of each expression.

Show your thinking using drawings, numbers, or words.

$4 + 9$
$15 - 3$
$7 + 6$
$17 - 9$
$14 + 5$
$12 - 4$
$6 + 12$
$16 - 5$

Practice Problem

Problem 1

Here are the numbers on seven cards:

1
2
3
5
6
7
9

Choose three of the numbers to add to get as close as you can to 20.
Write an equation to show your choice.