 # What is 1/11 + 9/12? 1 11
+
 9 12

## Step 1

We still have different denominators (bottom numbers), though, so we need to get a common denominator. This will make the bottom numbers match. Multiply the denominators together first. Now, multiply each numerator by the other term's denominator.

Now we multiply 1 by 12, and get 12, then we multiply 11 by 12 and get 132. Now for the second term. You multiply 9 by 11, and get 99, then multiply 11 by 12 and get 132. This gives us a new problem that looks like so:

 12 132
+
 99 132

## Step 2

Since our denominators match, we can add the numerators.

12 + 99 = 111

That gives us an answer of

 111 132

## Step 3

Can this fraction be reduced?

First, we attempt to divide it by 2...

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

Are both the numerator and the denominator evenly divisible by 3? Yes! So we reduce it:

 111 132
÷ 3 =
 37 44

Let's try dividing by that again...

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 37. So we're done reducing.

There you have it! Here's the final answer to 1/11 + 9/12

 1 11
+
 9 12
=
 37 44