1. Unit 2. Day 7.

2. Please get out paper for today’s lesson
Name
Date
Period
Topic: Adding & Subtracting Rational Numbers
7.NS.A.1 Apply and extend previous understandings of addition and subtraction to add and subtract rational numbers (fractions)

3. 4th, 5th, 6th Grade

4. Example A: Add or subtract. Write in simplest form.
4 8
1 2
3+1
2∙2 = = = = 8 8
2∙2∙2 4 8 2 2 2 4 2 2

5. Why don’t we add the denominators?
4 8
4 16

6. 5 9 − 2 9 2 7 + 3 7 Add or subtract. Write in simplest form.
Example B*:
Example C*:

7. Example B*: Add or subtract. Write in simplest form.
5 9 − 2 9
3 9
5−2
1 3 3 = = = = 9 9
3∙3 3 9 − − 3 3

8. Example C*: Add or subtract. Write in simplest form.
5 7
2+3 = = 7 7

9. 7th Grade

10. Example D: Add or subtract. Write in simplest form.
23 24 − 39 24
−16 24
23−39
− 2 3
− 2∙2∙2∙2 = = = = 24 24
2∙2∙2∙3 24 16 4 6 4 4 2 2 3 2 2 2 2 2

11. 5 32 − 33 32 − 11 16 − 1 16 Add or subtract. Write in simplest form.
Example E*:
− − 1 16
Example F*:
− − −7 12
Example G*:

12. Example E*: Add or subtract. Write in simplest form.
5 32 − 33 32
5−33
−28 32
− 7 8
−2∙2∙7 = = = = 32 32
2∙2∙2∙2∙2 32 28 4 8 4 7 2 4 2 2 2 2 2 2

13. Example F*: Add or subtract. Write in simplest form.
− − 1 16
−12 16
−11−1
− 3 4
−2∙2∙3 = = = = 16 16
2∙2∙2∙2 12 16 4 4 3 4 2 2 2 2 2 2

14. Example G*: Add or subtract. Write in simplest form.+
− − − 7 12
− − −7 12
−10 12
− 5 6
−17+7
−2∙5 = = = = 12 12
2∙2∙3 12 10 3 4 2 5 2 2

15. 10 6 3 2 5 2 Example H: Add or subtract. Write in simplest form.
5 1 6 −6 5 6
31 6
41 6 −
31−41
−10 6
−2∙5
− 5 3 = = = =
2∙3 6 6
−1 2 3 = 10 6 2 5 2 3

16. Example I*: Add or subtract. Write in simplest form.
−6 5 24
89 24
149 24 −
− 5 2
89−149
−60 24
−2∙2∙3∙5 = = = =
2∙2∙2∙3 24 24
−2 1 2 = 24 60 4 6 4 15 2 3 2 3 5 2 2 2