Unit 2 Contents

Find the Missing Numbers

Find the missing numbers. Be ready to explain your strategies.

1. = 10 + 6
2. = 20 + 6
3. 7 + 6 = + 6 + 6
4. 7 + 6 = + 4 + 6
5. 7 + 6 = + 3
6. 17 + 6 = 20 +
10. Show or tell your strategy for Question 9C.
1. = 20 + 4
2. 6 + 8 = 7 +
3. 6 + 8 = 6 + + 4
4. 6 + 8 = 4 + + 8
5. 6 + 8 = + 4
6. 16 + 8 = + 4
12. Show or tell your strategy for Question 11F.

Check-In: Questions 13–14

1. 9 + 6 = + 9
2. + 6 = 7 + 7
3. 17 + 3 + = 6 + 20
4. 9 + 4 = + 3
5. 8 + + 2 = 9 + 3
6. 8 + 4 = + 5
14. Show or tell your strategy for one of the problems in Question 13.

Use the Using Addition Strategies page in the Student Activity Book to practice adding with the making-tens strategy.