What is 2/5 + 5/10?

Let's add

Step 1

Our denominators (bottom numbers) don't match, so we can't add yet.

Since 5 is evenly divided by 10, we can multiply just one term to get a common denominator.

Multiply 2 by 2, and get 4, then we multiply 5 by 2 and get 10.

The problem now has new fractions to add:

Step 2

Since our denominators match, we can add the numerators.

4 + 5 = 9

The sum we get is

Step 3

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

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

Nope. Try the next prime number, 3...

Nope. Try the next prime number, 5...

Nope. Try the next prime number, 7...

Nope. Try the next prime number, 11...

No good. 11 is larger than 9. So we're done reducing.

Congratulations! Here's your final answer to 2/5 + 5/10