Unit 2. Day 14.

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: ÷ ∙

Today’s Lesson Multiplying Decimals Dividing Decimals

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 13 25 − 11.52 =

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 + =

Example C*: Multiply −1.6 ∙ 2.65 3 3 2 65 100 2 . 6 5 −1 6 10 1 . 6 × 1 − 16 10 265 100 1 1 5 9 ∙ 2 + 6 5 ∎ − 8 5 53 20 424 4 . 2 4 ∙ = − 100 − 106 25 −4 6 25 4.24 − =

Today’s Lesson Multiplying Decimals Dividing Decimals

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 =

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 =

Example F*: −6.25÷−0.75 −6.25 6.25 ÷ −0.75 0.75 + 8 . 3 3 3 −6 25 100 − 75 100 . 7 5 6 2 5 . − 6 0 0 2 5 − 625 100 − 75 100 − ÷ 2 2 5 2 5 − 2 2 5 − 25 4 − 4 3 − 3 4 2 5 100 ÷ ∙ = + 12 25 3 =8 1 3 =