What is 5/10 + 8/9?

Here's how we add

Step 1

We can't add two fractions with different denominators (the bottom number). So you need to get a common denominator - both bottom numbers need to match. 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 5 by 9, and get 45, then we multiply 10 by 9 and get 90.

Do the same for the second term. We multiply 8 by 10, and get 80, then multiply 10 by 9 and get 90.

So now our fractions look like this:

Step 2

Since our denominators match, we can add the numerators.

45 + 80 = 125

So the answer is:

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...

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...

Are both the numerator and the denominator evenly divisible by 5? Yes! So we reduce it:

So far so good... let's try to divide by that number again.

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. So next you try the next prime number, which is 19...

No good. 19 is larger than 18. So we're done reducing.

And we're done! Here's the final answer to 5/10 + 8/9