Exploring Multiplying Fractions

Fraction Exploration

Today we will add, subtract, multiply, and divide fractions in different forms

Multiplying Fractions

• Line the fractions together

• Multiply across

• Numerator times Numerator

• Denominator times Denominator

Multiple Choice

$$\frac{2}{3}\times\frac{4}{5}$$  Multiply straight across and solve.

• $$\frac{8}{15}$$  

• $$\frac{8}{3}$$  

• $$\frac{8}{5}$$  

• $$\frac{22}{15}$$  

Fill in the Blanks

$\frac{7}{9}\times\frac{4}{11}$ = 

Fill in the Blanks

$\frac{9}{7}\times\frac{5}{2}$  

What happened?

In the last question what happened when we multiplied improper fractions?

Adding and Subtracting Factions

• First make sure your fractions have the same denominator

• If the denominators are not the same you must find common denominator

• If the denominators are the same add/subtract the numerators

• Your solution will end with the common denominator at the bottom

Finding Common Denominators

• The easiest way is to multiply the denominators together

• But what you do to the denominator you must do to the numerator (that keeps the fraction equivalent)

• The other way is to find the LCD (least common denominator) This is for those who are truly ready

Multiple Choice

Are the denominators the same $$\frac{5}{13}+\frac{2}{13}$$ ? If not what is the common denominator?  If so what is the solution

• Yes,  $$\frac{7}{13}$$  

• Yes,  $$\frac{7}{26}$$  

• No, 26

• No, 169

Poll

Are the denominators the same $$\frac{7}{12}+\frac{1}{6}$$ ? If not what is the common denominator

• Yes 

• No, 6

• No, 72

• No, 12

When we find the common denominators we will make equivalent fractions. That means what we do to the bottom we do to the top.

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What is happening to my fraction?​

Multiple Choice

What does it look like with common denominators $$\frac{7}{12}+\frac{1}{6}$$ ?

• $$\frac{7}{12}+\frac{1}{12}$$  

• $$\frac{7}{12}+\frac{6}{12}$$  

• $$\frac{7}{12}+\frac{2}{12}$$  

Fill in the Blanks

Solve. Here is what we have determined $\frac{7}{12}+\frac{1}{6}=\frac{7}{12}+\frac{2}{12}=$  

Multiple Select

Which are considered common denominators for  $$\frac{3}{5}-\frac{1}{25}$$ ?

• 5

• 25

• 75

• 125

• 35

Multiple Choice

What does the equation look like after converting to common denominators  $$\frac{3}{5}-\frac{1}{25}$$ ?

• $$\frac{3}{5}-\frac{1}{5}$$  

• $$\frac{3}{25}-\frac{1}{25}$$  

• $$\frac{15}{25}-\frac{1}{25}$$  

• $$\frac{75}{125}-\frac{1}{125}$$  

Fill in the Blanks

Solve

$\frac{3}{5}-\frac{1}{25}$  

Poll

How is your understanding of adding and subtracting fractions? There will be another Quizizz with more problems for you to work on later.

• I'm Still Really Confused and Need More Help

• I get what to do but finding common denominators is hard

• I understand but would like more practice

• We were taught this but that did help me remember the rules

• Oh I am the master of fractions now

Division, you cannot divide with fractions

• That is correct you cannot technically divide with fractions

• To divide fractions

• Change the divisor to it's reciprocal (flip the fraction)

• Change from Dividing to Multiplying

Multiple Choice

What does $$\frac{7}{8}\div\frac{3}{8}$$ look like in multiplication form? 

• $$\frac{8}{7}\times\frac{8}{3}$$  

• $$\frac{8}{7}\times\frac{3}{8}$$  

• $$\frac{7}{8}\times\frac{8}{3}$$  

• $$\frac{7}{8}\times\frac{3}{8}$$  

Fill in the Blanks

Solve $\frac{7}{8}\div\frac{3}{8}$   

Multiple Choice

What does $$\frac{5}{21}\div\frac{2}{3}$$  look like in multiplication form?

• $$\frac{5}{21}\times\frac{3}{2}$$  

• $$\frac{5}{21}\times\frac{2}{3}$$  

• $$\frac{21}{5}\times\frac{2}{3}$$  

• $$\frac{21}{5}\times\frac{3}{2}$$  

Fill in the Blanks

Solve  $\frac{5}{21}\div\frac{2}{3}$  

Poll

How do you feel about Multiplying and dividing with fractions now? Yes there will be more practice later.

• I am the best at working those fractions

• I feel a little better but would like some more practice

• I get some of it but would like to see more review about it

• I'm lost can someone tell me what a denominator is