Multiplying and Dividing Rational Numbers

Reteach Multiplying and Dividing Rational Numbers

7.NS.2

​Happy Tuesday!

​4/16/2024

Learning Intention: 

We are learning to solve real world problems using multiplication and division of rational numbers.

Success Criteria:

• I can determine if the product or quotient will be positive or negative.

• I can convert a mixed number to an improper fraction.

• I can multiply positive and negative fractions.

• I can divide positive and negative fractions.

• I can simplify fractions.

Poll

Do you think the rules we used yesterday to multiply and divide integers can be used today when we work with fractions?

• Yes

• No

• Unsure

Our rules for multiplying integers apply to rational numbers also!

• Positive x Positive= Positive

• Negative x Negative= Positive

• Negative x Positive = Negative

Multiple Choice

Number 1 - we do:

A negative divided by a positive is a ________

• positive
• negative

Multiple Choice

Number 2 - we do:

What is the sign of the product of two positive numbers?

• Positive

• Negative

• Zero

Draw

Number 3 - I do:

$$\frac{2}{5}\ \times\ \frac{-1}{2}$$  

Draw

Number 4 - I do:

$$\frac{5}{7}\cdot-\frac{1}{10}$$  

Multiple Choice

Number 5 - we do:

Make sure your final answer is in simplest form.

• $$-\frac{7}{8}$$

• $$\frac{7}{8}$$

• $$-\frac{63}{72}$$

• $$\frac{63}{72}$$

Multiple Choice

Number 6 - we do:

$$\frac{-2}{3}\times\frac{2}{9}$$  

• $$-3$$  

• $$\frac{4}{27}$$  

• $$\frac{-4}{27}$$  

• $$3$$  

Multiple Choice

Number 7 - you do

What is the value of this expression?

• $$\frac{4}{12}$$

• $$\frac{-4}{12}$$

• $$\frac{1}{3}$$

• $$\frac{-1}{3}$$

Fill in the Blanks

Number 8 - you do:

$\frac{2}{7}\times\frac{1}{-3}=$

​I do

Fill in the Blanks

Number 9 - we do:

What is the value of this expression?

Type your answer as an improper fraction.
$-2\ \frac{1}{3}\times5$

Fill in the Blanks

Number 10 - you do:

$\left(-1\frac{1}{2}\right)\times\frac{8}{15}=$

​Dividing Fractions!

Rewrite the problem to multiplication by multiplying by the reciprocal.

Multiply the numerators.

Multiply the denominators.

Simplify if needed.

Draw

Number 11 - I do:

$$\left(-\frac{1}{4}\right)\div\left(-\frac{4}{3}\right)=$$

Multiple Choice

Number 12 - we do:

$$-\frac{1}{3}\div\frac{3}{4}$$  

• $$-\frac{3}{12}$$  

• $$\frac{4}{9}$$  

• $$\frac{1}{4}$$  

• $$-\frac{4}{9}$$  

Multiple Choice

Number 13 - you do:

$$\frac{1}{5}\div\frac{-2}{5}$$  

• $$\frac{-1}{2}$$  

• $$\frac{2}{10}$$  

• $$\frac{1}{5}$$  

• $$\frac{5}{10}$$  

Multiple Choice

Number 14 - you do:

- ³/₄ ÷ ¹/_{2
Simplify your answer.}

• $$-\frac{3}{8}$$

• $$-\frac{2}{6}$$

• $$-\frac{3}{2}$$

• $$-\frac{6}{4}$$

Learning Intention: 

We are learning to solve real world problems using multiplication and division of rational numbers.

Success Criteria:

• I can determine if the product or quotient will be positive or negative.

• I can convert a mixed number to an improper fraction.

• I can multiply positive and negative fractions.

• I can divide positive and negative fractions.

• I can simplify fractions.

Poll

How do you feel about the learning intention after today?

"We are learning to solve real world problems using multiplication and division of rational numbers."

• Unsure, still need help

• Okay, with some help

• Okay, with no help

• Great