math help

What is 3/18 + 2/12?

What is 3/18 + 2/12?

Here's how to add

3
18
+
2
12

Step 1

Can you add yet? Nope! The denominators don't match. We need a common denominator. So next we take both denominators and multiply them. Next, take each numerator and multiply it by the denominator of the other term.

So, we multiply 3 by 12, and get 36, then we multiply 18 by 12 and get 216.

3/18 times 12

Now for the second term. You multiply 2 by 18, and get 36, then multiply 18 by 12 and get 216.

2/12 times 18

We now have a new problem, that looks like this:

36
216
+
36
216

Step 2

Since our denominators match, we can add the numerators.

36 + 36 = 72

Answer:

72
216

Step 3

Now, do we need to simplify this fraction?

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

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

72
216
÷ 2 =
36
108

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

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

36
108
÷ 2 =
18
54

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

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

18
54
÷ 2 =
9
27

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 3...

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

9
27
÷ 3 =
3
9

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

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

3
9
÷ 3 =
1
3

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

No good. 3 is larger than 1. So we're done reducing.

And we're done! Here's the final answer to 3/18 + 2/12

3
18
+
2
12
=
1
3
© 2014 Randy Tayler