1. Unit 2. Day 12.

2. Please get out paper for today’s lesson
Name
Date
Period
Topic: Dividing Rational Numbers
7.NS.A.2 Apply and extend previous understandings of multiplication and division and of fractions to multiply and divide rational numbers

3. 6th Grade 5
3 4
3 4 ÷ 5 8
5 8
3∙8 24
2∙2∙2∙3
6 5 ÷ = ∙ = = = = 8
4∙5 20
2∙2∙5 𝑜𝑟
1 1 5 24 20 4 6 4 5 2 2 2 3 2 2
3 4 ∙ 8 5
3 2∙2
2∙2∙2 5
6 5
1 1 5 ∙ = = 𝑜𝑟

4. ∙ − − 3 4 ∙ 8 5 3 2∙2 2∙2∙2 5 = = 7th Grade 5 − 3 4 ÷− 5 8 3 4 − 5 8 ∙
3∙8 24
2∙2∙2∙3
6 5 ÷ ∙ − = = = = = 8
4∙5 20
2∙2∙5 24 20 4 6 4 5 2 2 2 3 2 2
3 4 ∙ 8 5
3 2∙2
2∙2∙2 5
6 5 ∙ = = −

5. Divide. Write in simplest form.
− 2 3 ÷− 10 9
Example A*:
− ÷ 35 14
Example B*:
3 8 9 ÷−1 3 4
Example C*:

6. Example A*: Divide. Write in simplest form.10
− 2 3 ÷− 10 9
2 3
10 9
2∙9 18
2∙3∙3
3 5 ÷ = ∙ = = = = 9
3∙10 30
2∙3∙5 18 30 2 9 3 10 3 3 2 5
2 3 ∙ 9 10
2 3
3∙3 2∙5
3 5 ∙ = =

7. Example B*: Divide. Write in simplest form.35
− ÷ 35 14
15 16
35 14
15∙14
210
2∙3∙5∙7 ÷ = ∙ = = = 14
16∙35
560
2∙2∙2∙2∙5∙7
3 8 = −
560
210 35 16 15 14 5 7 4 4 3 5 2 7 2 2 2 2
15 16 ∙ 14 35
3∙5 2∙2∙2∙2
2∙7 5∙7
− 3 8 ∙ = =

8. Example C*: Divide. Write in simplest form.− 7
3 8 9 ÷−1 3 4
3 8 9
−1 3 4
− 7 4
35 9
35∙4
140
2∙2∙5∙7 = = ÷ ∙ = =
3∙3∙7 4
9∙7 63
20 9
2 2 9 = − 𝑜𝑟 − 63
140 9 7 4 35 3 3 5 7 2 2
5∙7 3∙3
35 9 ∙− 4 7
2∙2 7
− 20 9
−2 2 9 ∙ = = 𝑜𝑟

9. Speed
Word problems
30 𝑚𝑖𝑙𝑒𝑠 1ℎ𝑜𝑢𝑟
𝑘𝑚/ℎ
𝑚𝑖 ℎ
𝑘𝑚 ℎ
𝑚𝑖÷ℎ
𝑘𝑚÷ℎ

10. 5 8
5 12
Example D*: Mr. Jordan walked miles in hr. What is his speed?
Speed
𝑚𝑖 ℎ𝑟 : ÷ = 5
5 8 ÷ 5 12
5 8
5 12
5∙12
3 2 60
2∙2∙3∙5 ÷ = ∙ = = = = 12
8∙5 40
2∙2∙2∙5
1 1 2 = 60 40 6 10 4 10 2 3 2 5 2 2 2 5

11. Example E: Mr Jordan has 2 4 9 cups of jelly beans
Example E: Mr Jordan has cups of jelly beans. If he divides the jelly beans into cup containers, how many containers will he need?
2 4 9
2 4 9
1 3
1 3
22 9
3 1
66 9
2∙3∙11 3∙3
22 3 ÷ ÷ = ∙ = = =
7 1 3

12. “How many times larger?”
Word problems

13. Example F. : Mr Jordan makes breakfast and uses 5 1 4 cups of rice. Mr
Example F*: Mr Jordan makes breakfast and uses cups of rice. Mr. Yost only uses cup of rice. How many times larger is the amount of rice used by Mr. Jordan?
5 1 4
5 1 4
3 4
3 4
21 4
4 3
84 12
2∙2∙3∙7 2∙2∙3
7 1 ÷ ÷ = ∙ = = = = 7