1. Unit 2. Day 13.

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. Q: What is a rational number?
A: A number that can be written as a fraction 𝑝 𝑞
− 5 7
− 5 7
2 3
2 3
−4 5 6
−4 5 6
0.875
0.875
−16. 3
−16. 3
Before we multiplied: ∙ ÷
Today: ÷ ∙

4. Today’s Lesson
Multiplying Decimals
Dividing Decimals

5. Example A: Multiply 4.8 ∙ −2.4
4.8 ∙
−2.4 1 3
4 8 10
−2 4 10
4 . 8
2 . 4 ×
48 10
− 24 10 1 ∙ 1 9 2 9 6 ∎ +
24 5
− 12 5
288 ∙ = − 25 1 1 . 5 2 − −
11.52 =

6. 6 . 4 0 . 2 1 2 8 ∎ . 1 2 8 1.28 × + Example B*: Multiply −6.4 ∙ −0.2
−6 4 10
− 2 10
6 . 4
0 . 2 ×
− 64 10
− 2 10 1 2 8 ∙ ∎ + 32
− 32 5
− 1 5 = + ∙ 25 1 . 2 8
1 7 25
1.28 + =

7. Example C*: Multiply −1.6 ∙ 2.653 3
−1 6 10
1 . 6 × 1
− 16 10 1 1 5 9 ∙ 2 + 6 5 ∎
− 8 5
53 20
424 4 . 2 4 ∙ = −
100 −
−4 6 25
4.24 − =

8. Today’s Lesson
Multiplying Decimals
Dividing Decimals

9. Example D:
−3.6÷0.5
−3.6
3.6 ÷
0.5
0.5 . − 7 2
−3 6 10
5 10 . 5
3 6 . −
3 5 1
− 36 10
5 10 − ÷
1 0
− 18 5
2 1
1 2 36 ÷ ∙ = − 5
−7 1 5 =

10. Example E*:
−4.8÷1.5
−4.8
4.8 ÷
1.5
1.5 . − 3 2
−4 8 10
1 5 10 1 . 5
4 8 . −
4 5 3
− 48 10
15 10 − ÷
3 0
− 24 5
2 3
3 2 48 ÷ ∙ = − 15
− 16 5
−3 1 5 =

11. Example F*:
−6.25÷−0.75
−6.25
6.25 ÷
−0.75
0.75 + 8 . 3 3 3 − − .
7 5
6 2 5 . −
2 5 − − − ÷
2 2 5
2 5 −
2 2 5
− 25 4
− 4 3
− 3 4
2 5
100 ÷ ∙ = + 12
25 3
=8 1 3 =