Numerator and Denominator of a Fraction

U02_l1_T1_we1 Numerator and Denominator of a Fraction

We're asked to identify the numerator and denominator

in the fraction three over four, or three-fourths.

Let's rewrite this, so it's nice and big.

So let me just write the fraction.

So we have three over

three over four.

Three over four.

Now, they want us to identify the numerator and denominator,

The Numerator.

So the numerator is just the number on top.

So the numerator is the three right there.

And then they want us to find the denominator.

The denominator is just the number on the bottom.

It's the four.

So if they say, what's the numerator? Three.

What's the denominator? It's four.

Just the number on the bottom.

They could have just called this the

number on the bottom,

they could have just called this

the number on the top.

Now to think about what this represents,

what this fraction represents,

you can think of it as three out of four

pieces of a pie, that's how I think about it.

You can imagine, the denominator tells us

What are we taking a fraction out of?

Or how many pieces are there?

So let's imagine a pie like this.

So we could draw it like,

well we could draw it as a square pie,

So we could draw it as a square pie,

So this is what the denominator represents,

this is what the number on the bottom represents.

And then three says,

We are representing three of those four pieces.

So this three tells us that out of four possible ones,

we are using three.

Or maybe we're eating three.

So you can imagine someone says,

"I ate three-fourths of a pie"

This would be read as three-fourths,

they're eating the blue portion of the pie

if we cut it this way.

If we imagine a round pie,

it would look like this--

Let me draw a round pie...

So that is my round pie.

Let me cut it into four equal pieces.

Or roughly equal pieces.

And if someone says,

"I ate three-fourths of this pie"

where the three is the numerator,

and then the four, and you'd

read that as three-fourths,

The four is the denominator.

They would eat this much of the pie.

They would eat three of the four pieces.

They would eat three of the four.

So this is one piece, this is two pieces,

and this is three pieces.

So you can imagine the four,

the denominator,

represents the total number of pieces

in the pie, and the three represents

how many of those we ate.