math help

What is 9/12 + 5/11?

What is 9/12 + 5/11?

This is how you add

9
12
+
5
11

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 9 by 11, and get 99, then we multiply 12 by 11 and get 132.

9/12 times 11

Now for the second term. You multiply 5 by 12, and get 60, then multiply 12 by 11 and get 132.

5/11 times 12

This gives us a new problem that looks like so:

99
132
+
60
132

Step 2

Since our denominators match, we can add the numerators.

99 + 60 = 159

So what's the answer so far?

159
132

Step 3

Can this fraction be reduced?

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

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

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

159
132
÷ 3 =
53
44

Now, try the same number again.

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

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

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

Nope. Try the next prime number, 13...

Nope. Try the next prime number, 17...

Nope. Try the next prime number, 19...

Nope. Try the next prime number, 23...

Nope. Try the next prime number, 29...

Nope. Try the next prime number, 31...

Nope. Try the next prime number, 37...

Nope. Try the next prime number, 41...

Nope. Try the next prime number, 43...

Nope. Try the next prime number, 47...

No good. 47 is larger than 44. So we're done reducing.

Congratulations! Here's your final answer to 9/12 + 5/11

9
12
+
5
11
=
53
44
© 2014 Randy Tayler