 # What is 7/16 - 4/10? Here's how to subtract 4/10 from 7/16:

 7 16
 4 10

## 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 7 by 10, and get 70.

Then we multiply 4 by 16, and get 64.

Next we give both terms new denominators -- 16 × 10 = 160.

So now our fractions look like this:

 70 160
 64 160

## Step 2

Since our denominators match, we can subtract the numerators.

70 − 64 = 6

 6 160

## 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:

 6 160
÷ 2 =
 3 80

Let's try dividing by 2 again...

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

Nope! So now we try the next greatest prime number, 5...

No good. 5 is larger than 3. So we're done reducing.

There you have it! The final answer is:
 7 16
 4 10
=
 3 80