 # What is 4/6 - 4/12? Here's how to subtract 4/12 from 4/6:

 4 6
 4 12

## 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 4 by 12, and get 48.

Then we multiply 4 by 6, and get 24.

Next we give both terms new denominators -- 6 × 12 = 72.

So now our fractions look like this:

 48 72
 24 72

## Step 2

Since our denominators match, we can subtract the numerators.

48 − 24 = 24

 24 72

## 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:

 24 72
÷ 2 =
 12 36

Let's try dividing by 2 again...

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

 12 36
÷ 2 =
 6 18

Let's try dividing by 2 again...

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

 6 18
÷ 2 =
 3 9

Let's try dividing by 2 again...

Nope! So now we try the next greatest prime number, 3...

Are both the numerator and the denominator evenly divisible by 3? Yes! So we reduce it:

 3 9
÷ 3 =
 1 3

Let's try dividing by 3 again...

No good. 3 is larger than 1. So we're done reducing.

There you have it! The final answer is:
 4 6
 4 12
=
 1 3