13 + 21 + 32 = ＿.
13 plus 21 plus 32 equals what?
In order to add these numbers, we could simply plug it into a calculator. But what if we didn’t have one? If we didn’t, it would be wise to stack them on top of each other like this.
Now, we will add the ones column together. Three plus one plus two is six. Now, we will add the tens column together. One plus two plus three, which is equal to six, making our final answer equal to 66.