 # What is 2/3 + 4/5? 2 3
+
 4 5

## Step 1

Of course, you can't add two fractions if the denominators (bottom numbers) don't match. To get a common denominator, multiply the denominators together. Then we fix the numerators by multiplying each one by their other term's denominator.

Now you multiply 2 by 5, and get 10, then we multiply 3 by 5 and get 15. Do the same for the second term. We multiply 4 by 3, and get 12, then multiply 3 by 5 and get 15. The problem now has new fractions to add:

 10 15
+
 12 15

## Step 2

Since our denominators match, we can add the numerators.

10 + 12 = 22

The sum we get is

 22 15

## 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. So next you try the next prime number, which is 17...

No good. 17 is larger than 15. So we're done reducing.

And we're done! Here's the final answer to 2/3 + 4/5

 2 3
+
 4 5
=
 22 15 