Addition and Subtraction Facts to 20

CHAPTER

8

Circle to make a 10. Add.

Lesson 1 Ways to Add (Part 1)

1.

5 + 6 =

2.

9 + 7 =

Make a 10.Then add.

3. +

4 + 8 = 2 + 10

2 2

=

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4. +

6 + 7 = +

=

5.

+

3 + 9 = +

=

Make a 10.Then add.

6. 4 + 8 =

7. 6 + 8 =

Chapter 8 Lesson 1118

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Make a 10.Then add.

8. 6 + 5 =

9. 9 + 9 =

Color the car that gives the least answer.

10.

8 + 9 6 + 7 9 + 5 7 + 8

Color the car that gives the greatest answer.

11.

7 + 5 9 + 7 5 + 9 8 + 2

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Complete the addition sentences.

12.

7 + 6 =

13.

8 + 4 =

14.

7 + 8 =

15.

9 + 3 =

Chapter 8 Lesson 1120

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Lesson 1 Ways to Add (Part 2)Group the number into a 10 and ones.Then add.

1.

17 + 2 =

2.

11 + 4 =

3.

14 + 3 =

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4.

6 + 12 =

5.

3 + 11 =

Add.

6. 13 + 6 =

8. 11 + 5 =

10. 8 + 11 =

7. 15 + 3 =

9. 3 + 13 =

11. 12 + 5 =

Chapter 8 Lesson 1122

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Lesson 1 Ways to Add (Part 3)Match.

1.

8 + 8 4

2.

4 + 4 18

3.

169 + 9

4.

2 + 2 10

5.

7 + 7 14

6.

5 + 5 8

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Add the doubles-plus one numbers. Use doubles facts to help you.

7. 4 + 5 = Doubles fact:

+ =

8. 8 + 9 = Doubles fact:

+ =

9. 5 + 6 = Doubles fact:

+ =

10. 7 + 8 = Doubles fact:

+ =

11. 3 + 4 = Doubles fact:

+ =

12. 6 + 7 = Doubles fact:

+ =

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Chapter 8 Lesson 1

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Lesson 2 Ways to SubtractGroup the numbers into a 10 and ones.Then subtract.

1.

17 – 5 =

2.

15 – 3 =

3.

18 – 5 =

4.

16 – 5 =

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Group the numbers into a 10 and ones.Then subtract.

5.

10

16 – 6 =

6. 13 – 2 =

7. 14 – 3 =

8. 17 – 5 =

9. 20 – 6 =

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Chapter 8 Lesson 2

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Group the numbers into a 10 and ones.Then subtract.

Example

11 – 4 = ? 10 – 4 = 6

1 + 6 = 7

So, 11 – 4 = 7.10 1

10.

15 – 7 = ? – =

+ =

So, 15 – 7 = .

11.

13 – 4 = ? – =

+ =

So, 13 – 4 = .

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12.

12 – 6 = ? – =

+ =

So, 12 – 6 = .

13.

14 – 6 = ? – =

+ =

So, 14 – 6 = .

14.

17 – 8 = ? – =

+ =

So, 17 – 8 = .128

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Chapter 8 Lesson 2

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Use number bonds to subtract.

15.

1010

20 − 6 =

16. 18 − 6 =

17. 15 − 9 =

18. 12 − 9 =

19. 13 − 5 =

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20. 15 – = 10

21. 16 − = 13

22. 14 − = 8

23. 11 − = 5

24. 17 − = 9

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Chapter 8 Lesson 2

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Lesson 3 Real-World Problems:Addition and Subtraction Facts

Solve.Write a number sentence.

1. Mark collects 10 seashells. Ben collects 2 seashells fewer than Mark. How many seashells does Ben collect?

=

Ben collects seashells.

2. 7 boys are playing. 6 boys join them. How many boys are playing now?

=

There are boys playing now.

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3. There are 16 apples. 4 of them are green. How many apples are not green?

=

apples are not green.

4. Pamela has 12 beads. Tina has 8 beads more than Pamela. How many beads does Tina have?

Tina has beads.

5. Andrew caught some butterfl ies. 8 of them fl ew away. He had 4 left. How many butterfl ies did Andrew catch?

Andrew caught butterfl ies.

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Chapter 8 Lesson 3

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Put on Your Thinking Cap!

1.

Albert Jenny May

May has 10 marbles fewer than Albert. May has 5 marbles more than Jenny. Albert gives 4 marbles to Jenny. May gives another 6 marbles to Jenny. Jenny has 13 marbles now.

Find the number of marbles each of them had at fi rst.

Jenny had marbles.

May had marbles.

Albert had marbles.

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2. Ben, Caleb, and Derek collect seashells at the beach. Ben has 8 seashells. Caleb has 10 more seashells than Ben but only

6 more than Derek. How many seashells does each of them have?

Ben has seashells.

Caleb has seashells.

Derek has seashells.

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Chapter 8 Put on Your Thinking Cap!

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