 # What is 2/3 + 9/12? Here's how you add

 2 3
+
 9 12

## Step 1

We have to make sure the denominators are equal.

Since 3 is evenly divided by 12, we can multiply just one term to get a common denominator.

Multiply 2 by 4, and get 8, then we multiply 3 by 4 and get 12. The problem now has new fractions to add:

 8 12
+
 9 12

## Step 2

Since our denominators match, we can add the numerators.

8 + 9 = 17

This yields the answer

 17 12

## Step 3

The last step is to reduce the fraction if we can.

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

No good. So next you try the next prime number, which is 3...

No good. So next you try the next prime number, which is 5...

No good. So next you try the next prime number, which is 7...

No good. So next you try the next prime number, which is 11...

No good. So next you try the next prime number, which is 13...

No good. 13 is larger than 12. So we're done reducing.

And we're done! Here's the final answer to 2/3 + 9/12

 2 3
+
 9 12
=
 17 12
© 2014 Randy Tayler