1. says I should “change” my shirt before she “flips” her lid!
Dividing Fractions
Made Easy!
Using…
keep
My momma
says I should “change” my shirt before she “flips” her lid!
Change!
Flip!
CCSS 5NBT.B.7
© Mike’s Math Mall

2. doesn’t remember what he had for breakfast!
Dividing Fractions
Because with a little change to a division of fractions’ problem, you’ll be right back to multiplying!
Dividing fractions sounds hard, but if you remember how to multiply fractions, then you’re in luck!
Sparky
doesn’t remember what he had for breakfast!
We better review!

3. Multiplying Fractions Review
To multiply fractions, we multiply numerator by numerator and denominator by denominator.
𝟐 𝟑 × 𝟑 𝟒 = 𝟔 𝟏𝟐
÷𝟔 ÷𝟔 =
𝟏 𝟐
Or you can “cross-cancel” to simplify:
Don’t forget to simplify!
𝟐 𝟑 × 𝟑 𝟒 1
= 𝟏 𝟐 1 1 2

4. Multiplying Fractions Review
And that
cross-cancelling
thing is sweet! Can we
do another one…
pleeeease?
Now I
remember how
to multiply
fractions!
Awesome!
Absolutely! But let’s look at how to divide fractions first!

5. Dividing Fractions
By using the phrase, “keep, change, flip,” we can easily turn a division of fractions’ problem into a multiplication problem.
Dividing fractions is a tricky concept. It’s actually easier to multiply them.
“Keep, change, flip” means multiply by the reciprocal in the big leagues.
3 ft 1 in
I’m a
big leaguer!
Yeah, we can tell!
(wink-wink)

6. Remember! Think “keep, change, flip”!
Dividing Fractions
𝟐 𝟑 ÷ 𝟑 𝟒
Let’s try one!
𝟐 𝟑
Keep– Keep the first fraction
Remember! Think “keep, change, flip”!
𝟐 𝟑 ×
Change – Change the division
symbol to multiplication:
Flip – Flip (invert) the second
fraction:
𝟐 𝟑 ×
𝟒 𝟑

7. And just like that, we’re back
Dividing Fractions
And just like that, we’re back
to multiplying!
𝟐 𝟑 ÷ 𝟑 𝟒 =
𝟖 𝟗
𝟐 𝟑 × 𝟒 𝟑 =
Since 𝟖 𝟗 is simplified,
we’re done!
That “keep,
change, flip” thing
is kinda cool, but I’m
not quite sure
I have it.
Then let’s
do another one!

8. Dividing Fractions 𝟒 𝟗 ÷ 𝟖 𝟏𝟓 𝟒 𝟗 𝟒 𝟗 × 𝟒 𝟗 𝟏𝟓 𝟖 × Keep: Change: Flip:
Give this a try!
𝟒 𝟗
Keep:
Change:
𝟒 𝟗 ×
Flip:
𝟒 𝟗 ×
𝟏𝟓 𝟖

9. Or we could cross-cancel!
Dividing Fractions
𝟒 𝟗 × 𝟏𝟓 𝟖 =
𝟔𝟎 𝟕𝟐
𝟒 𝟗 ÷ 𝟖 𝟏𝟓 =
Simplify!
𝟔𝟎÷𝟐 𝟕𝟐÷𝟐 =
𝟑𝟎÷𝟔 𝟑𝟔÷𝟔 =
𝟓 𝟔
Or we could cross-cancel!
I tried
to simplify my sister once.
Momma
cross-cancelled that plan!
𝟒 𝟗 × 𝟏𝟓 𝟖
= 𝟓 𝟔 1 5 3 2
Ouch!
Oh, yeah? How’d that end up?

10. Show Your Stuff!
Divide the following fractions. Simplify answers when necessary.
𝟒 𝟓
1) 𝟏 𝟐 ÷ 𝟐 𝟑 =
𝟑 𝟒
2) 𝟑 𝟓 ÷ 𝟑 𝟒 =
𝟐 𝟑
𝟖 𝟏𝟓
3) 𝟐 𝟔 ÷ 𝟏 𝟐 =
4) 𝟏 𝟑 ÷ 𝟓 𝟖 =
𝟏 𝟐
𝟒 𝟓
5) 𝟒 𝟗 ÷ 𝟖 𝟗 =
6) 𝟕 𝟏𝟎 ÷ 𝟏𝟒 𝟏𝟔 =

11. Dividing Fractions How’d you do on the practice problems, Sparky?
Why? Do you have big plans later?
I did great!
But what about
dividing fractions with
whole numbers?
Ok! But
will this take
long?
Four words… Burrito Factory… free samples.
That’s actually a great question! We better take a look at that.
We’ll hurry!

12. First, we need to change the 3 into a fraction by placing it over 1.
Dividing Fractions
𝟓 𝟖 ÷
÷ 𝟑 𝟏
Take a look at this one! 𝟑
First, we need to change the 3 into a fraction by placing it over 1.
𝟓 𝟖
Now we’re ready for
keep, change, flip!
Keep:
𝟓 𝟖 ×
Change:
𝟓 𝟖 × 𝟏 𝟑
= 𝟓 𝟐𝟒
Flip:

13. Here’s another example: A few more peppery practice problems!
Dividing Fractions
Here’s another example:
𝟒 𝟏 ÷
÷ 𝟐 𝟕 𝟒
𝟒 𝟏 ÷ 𝟐 𝟕 =
𝟒 𝟏 × 𝟕 𝟐
Create a fraction!
= 𝟏𝟒 𝟏 2
=14 1
Some free,
spicy, beefy burrito
samples! Do
you smell that?
Hey,
that wasn’t so bad!
Very
funny!
What?
A few more peppery practice problems!
No, but do you smell that?
I never said it would be!
Smell what?

14. Show Your Stuff!
Divide the following fractions. Simplify answers when necessary.
1) 𝟒 𝟓 ÷4=
𝟏 𝟓
2) 6÷ 𝟑 𝟒 = 8
Extension) 1 𝟑 𝟒 ÷2 𝟓 𝟖 =
𝟕 𝟒 ÷ 𝟐𝟏 𝟖 = 2
𝟐 𝟑 1
𝟕 𝟒 × 𝟖 𝟐𝟏 = 1 3

15. And how’s that working out?
Dividing Fractions
Remember, Sparky!
You can only cross-cancel after a division of fractions’ problem has been changed to multiplication.
I’m always
trying to remember
to not hold in my
sneezes.
Have you
seen the size of
my head?
And how’s that working out?
Point taken!
© Mike’s Math Mall

16. Dividing Mixed Numbers
You must first change the mixed number into an improper fraction.
Ex. 6 𝟏 𝟐 ÷ ÷ =
Once you have converted from a mixed number, you must KEEP, CHANGE, FLIP.
13 2 ÷ × = =
***Don’t forget to convert back to a mixed number and simplify if necessary.
Keep, Change, Flip

17. Show Your Stuff!
Divide the following fractions. Simplify answers when necessary.