 # What is 7/10 + 5/8? 7 10
+
 5 8

## 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 7 by 8, and get 56, then we multiply 10 by 8 and get 80. Do the same for the second term. We multiply 5 by 10, and get 50, then multiply 10 by 8 and get 80. The problem now has new fractions to add:

 56 80
+
 50 80

## Step 2

Since our denominators match, we can add the numerators.

56 + 50 = 106

The sum we get is

 106 80

## Step 3

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

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:

 106 80
÷ 2 =
 53 40

Let's try dividing by that again...

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

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

Nope! So now we try the next greatest prime number, 7...

Nope! So now we try the next greatest prime number, 11...

Nope! So now we try the next greatest prime number, 13...

Nope! So now we try the next greatest prime number, 17...

Nope! So now we try the next greatest prime number, 19...

Nope! So now we try the next greatest prime number, 23...

Nope! So now we try the next greatest prime number, 29...

Nope! So now we try the next greatest prime number, 31...

Nope! So now we try the next greatest prime number, 37...

Nope! So now we try the next greatest prime number, 41...

No good. 41 is larger than 40. So we're done reducing.

There you have it! Here's the final answer to 7/10 + 5/8

 7 10
+
 5 8
=
 53 40