Imagine you and a friend went out for pizza. You ate 
of the pizza. Your friend ate 
of the pizza. What would you do if you wanted to know how much the two of you ate all together? To solve the problem, you would need to find the least common denominator.
Let's write out the problem in a column:
Now let's solve the problem. The first step is to find the least common denominator. What's the least common denominator for 3 and 2? It's 6.
To change each denominator to 6, we need to multiply. Let's look at 
. We multiply the denominator by 2 to make 6. Then we need to multiply the top number (numerator) by 2 to match. We end up with 2 as the top number.
Our new fraction is 
.
Let's look at 
. We multiply the denominator by 3 to make 6. Then we need to multiply the numerator by 3 to match. We end up with 3 as the top number.
Our new fraction is 
.
Here's our new equation:
We simply add the top numbers, 2 + 3, to get 5. Our answer is 
. This is how much of the pizza you and your friend ate.
