 # What is 8/12 - 4/8? Here's how to subtract 4/8 from 8/12:

 8 12
 4 8

## Step 1

We can't subtract two fractions with different denominators. So you need to get a common denominator. To do this, you'll multiply the denominators times each other... but the numerators have to change, too. They get multiplied by the other term's denominator.

So we multiply 8 by 8, and get 64.

Then we multiply 4 by 12, and get 48.

Next we give both terms new denominators -- 12 × 8 = 96.

So now our fractions look like this:

 64 96
 48 96

## Step 2

Since our denominators match, we can subtract the numerators.

64 − 48 = 16

 16 96

## Step 3

Last of all, we need to simplify the fraction, if possible. Can it be reduced to a simpler fraction?

To find out, we try dividing it by 2...

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

 16 96
÷ 2 =
 8 48

Let's try dividing by 2 again...

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

 8 48
÷ 2 =
 4 24

Let's try dividing by 2 again...

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

 4 24
÷ 2 =
 2 12

Let's try dividing by 2 again...

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

 2 12
÷ 2 =
 1 6

Let's try dividing by 2 again...

No good. 2 is larger than 1. So we're done reducing.

There you have it! The final answer is:
 8 12
 4 8
=
 1 6