Grade 2 Unit 9
Lesson 1: Sums and Differences Within 20
CC BY 2021 Illustrative Mathematics®
Grade 2 Unit 9
Lesson 1: Sums and Differences Within 20
CC BY 2021 Illustrative Mathematics®
Find the value of each expression mentally.
10 - 5
11 - 5
12 - 6
13 - 6
Find the value of each sum mentally.
Circle any sum that you did not remember right away.
Directions:
• Spin the top spinner to get your total.
• Spin the bottom spinner to get one addend.
• Find the unknown addend.
Write an equation to show how you found the unknown addend.
Find the value of each expression.
11 - 5
12 - 3
16 - 8
9 + 3
8 + 8
6 + 6
9 + 9
7 + 7
8 + 8
5 + 5
9 + 8
7 + 8
8 + 5
6 + 5
7 + 6
7 + 9
6 + 8
9 + 2
7 + 5
8 + 4
2 + 9
9 + 7
6 + 9
8 + 3
9 + 4
8 + 6
3 + 9
5 + 6
9 + 5
5 + 9
9 + 6
8 + 9
6 + 7
5 + 7
8 + 7
13 - 8