math help

What is 3/18 + 9/11?

What is 3/18 + 9/11?

This is how to add

3
18
+
9
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 3 by 11, and get 33, then we multiply 18 by 11 and get 198.

3/18 times 11

Now for the second term. You multiply 9 by 18, and get 162, then multiply 18 by 11 and get 198.

9/11 times 18

This gives us a new problem that looks like so:

33
198
+
162
198

Step 2

Since our denominators match, we can add the numerators.

33 + 162 = 195

That gives us an answer of

195
198

Step 3

Can this fraction be reduced?

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

No good. So next you try the next prime number, which is 3...

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

195
198
÷ 3 =
65
66

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 5...

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. So next you try the next prime number, which is 23...

No good. So next you try the next prime number, which is 29...

No good. So next you try the next prime number, which is 31...

No good. So next you try the next prime number, which is 37...

No good. So next you try the next prime number, which is 41...

No good. So next you try the next prime number, which is 43...

No good. So next you try the next prime number, which is 47...

No good. So next you try the next prime number, which is 53...

No good. So next you try the next prime number, which is 59...

No good. So next you try the next prime number, which is 61...

No good. So next you try the next prime number, which is 67...

No good. 67 is larger than 65. So we're done reducing.

And we're done! Here's the final answer to 3/18 + 9/11

3
18
+
9
11
=
65
66
© 2014 Randy Tayler