Dividing Fractions

Dividing Fractions

Multiple Choice

When dividing with mixed numbers, you have to _______ before you start.

• Change mixed numbers to improper fractions

• Change improper fractions to mixed numbers

• Divide the whole numbers first

Multiple Choice

Change this mixed number to an improper fraction

 $3\ \frac{5}{7}$  

•  $\frac{26}{7}$  

•  $\frac{15}{7}$  

•  $\frac{21}{7}$  

Multiple Choice

Change this mixed number to an improper fraction

 $8\ \frac{1}{2}$  

•  $\frac{16}{2}$  

•  $\frac{17}{2}$  

•  $\frac{8}{2}$  

Multiple Choice

When dividing fractions, we use KCF:

• Keep, Circle, Flip

• Keep, Change, Fraction

• Keep, Change, Flip

Multiple Choice

Keep, Change, Flip

 $\frac{3}{7}\div\frac{8}{21}$  

•  $\frac{3}{7}\times\frac{21}{8}$  

•  $\frac{7}{3}\times\frac{8}{21}$  

•  $\frac{3}{7}\div\frac{21}{8}$  

After you KCF, follow the steps for multiplication

• Cross- cancel

• Multiply straight across

• Simplify if needed

Multiple Choice

Can you cross- cancel before multiplying these fractions?

 $\frac{3}{4}\times\frac{11}{12}$  

• Yes, you can cancel 4 and 11

• Yes, you can cancel 3 and 12

• Yes, you can cancel all of the numbers

• No, you cannot cancel 

Multiple Choice

Can you cross cancel these fractions?

 $\frac{21}{24}\times\frac{6}{7}$  

• Yes, you can cancel 21 and 7

• Yes, you can cancel 24 and 6

• Yes, you can cancel both

• No, you can't cancel

Multiple Choice

Can you cross cancel these fractions?

 $\frac{7}{8}\times\frac{17}{23}$  

• Yes, you can cancel 7 and 23

• Yes, you can cancel 8 and 17

• Yes, you can cancel both

• No, you can't cancel

Multiple Choice

Multiply

 $\frac{3}{4}\times\frac{1}{5}$  

•  $\frac{3}{20}$  

•  $\frac{3}{9}$  

•  $\frac{15}{4}$  

Multiple Choice

Simplify

 $\frac{15}{25}$  

• It is simplified

•  $\frac{3}{5}$  

•  $\frac{5}{5}$  

Multiple Choice

Simplify

 $\frac{8}{9}$  

• It is simplified

•  $\frac{2}{3}$  

Multiple Choice

Simplify

 $\frac{17}{8}$  

• It is simplified

•  $2\ \frac{1}{8}$  

•  $1\ \frac{2}{8}$  

Multiple Choice

Follow all steps and divide:

 $\frac{8}{21}\div\frac{6}{7}$  

•  $\frac{48}{147}$  

•  $\frac{56}{126}$  

•  $\frac{4}{9}$  

Multiple Choice

Follow all steps to divide:

 $\frac{3}{5}\div\frac{21}{25}$  

•  $\frac{5}{7}$  

•  $\frac{7}{5}$  

•  $\frac{75}{105}$  

Multiple Choice

Follow all steps to divide

 $3\ \frac{3}{4}\div2\ \frac{7}{8}$  

•  $6\ \frac{21}{32}$  

•  $\frac{30}{23}$  

•  $1\ \frac{7}{23}$  

Poll

How do you feel about dividing fractions over-all?

• Great! It's easy

• Okay, I'm getting better

• Okay, but I need more practice

• Not good, I need some help

Poll

What are you having trouble with? (You can pick more than one!)

• Nothing! I feel good about it.

• Changing mixed numbers to improper fractions

• Keep-Change-Flip

• Cross-Cancelling

• Simplifying