Dividing Fractions is Fun!!

Dec2

One way to make you divide fractions easily is to remember and master the steps by steps process on how to do it so here are some fun ways to do it. 

To help you remember:

♫ “Dividing fractions, as easy as pie,
Flip the second fraction, then multiply.
And don’t forget to simplify,
Before it’s time to say goodbye” ♫

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Now that you remember all the steps let us have some exercises to test your skills.

1. How Many?

20 divided by 5 is asking “how many 5s in 20?” (=4) and so:

1/2  ÷  1/6 is really asking: how many 16s in 12 ?

Now look at the pizzas below … how many “1/6th slices” fit into a “1/2 slice”?

How many 1/6 in 3/6 ? Answer: 3

So now you can see why 1/2  ÷  1/6 = 3

2. 1/8  ÷  1/4

Step 1. Turn the second fraction upside down (the reciprocal):

1/4  becomes  4/1

Step 2. Multiply the first fraction by that reciprocal:

1/8  ×  4/1 = 1 × 4/8 × 1 = 4/8

Step 3. Simplify the fraction:

4/8  =  1/2

Fractions and Whole Numbers
What about division with fractions and whole numbers?

Make the whole number a fraction, by putting it over 1.

Example: 5 is also 5/1
Then continue as before.

Example:
2/3  ÷  5

Make 5 into 511 :

2/3  ÷  5/1

Then continue as before.

Step 1. Turn the second fraction upside down (the reciprocal):

5/1 becomes 1/5

Step 2. Multiply the first fraction by that reciprocal:

2/3 × 1/5 = 2 × 1/3 × 5 = 215

Step 3. Simplify the fraction:

The fraction is already as simple as it can be.

Answer = 2 1/5
Example:
3  ÷  1/4

Make 3 into 3/1 :

31  ÷  1/4

Then continue as before.

Step 1. Turn the second fraction upside down (the reciprocal):

1/4 becomes 4/1

Step 2. Multiply the first fraction by that reciprocal:

3/1 × 4/1 = 3 × 4/1 × 1 = 12/1

Step 3. Simplify the fraction:

12/1 = 12

And Remember …
You can rewrite a question like “20 divided by 5” into “how many 5s in 20″So you can also rewrite “3 divided by ¼” into “how many ¼s in 3” (=12)

Why Turn the Fraction Upside Down?
Because dividing is the opposite of multiplying!

A fraction says to:

  •  multiply by the top number
  • divide by the bottom numberk

But for DIVISION we:

divide by the top number
multiply by the bottom number
Example: dividing by 5/2 is the same as multiplying by 2/5

fraction-multiply-divide-2

So instead of dividing by a fraction, it is easier to turn that fraction upside down, then do a multiply.

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