You have learned that when you add one number to another, you find the total of both n­umbers put together. You also know that numbers have place values: ones, tens, ­and hundreds.

Now you can use these place values to solve addition problems. This is called column addition.

Some addition problems only have a digit in the ones column. Look at this addition problem:

9

+ 7

What is the answer to this addition problem? It's 16.

9

+ 7

16

How many tens are in the answer? There is one ten. How many ones? There are six ones.

Some problems have digits in the tens place (tens column). With these kinds of problems, first we work with the digits in the ones place (ones column). Then we add the digits in the tens place. Sometimes there will be digits in the hundreds place (hundreds column), too. Add those digits last.

Look at this addition problem:

13

+ 22

First add the digits in the ones place. What is 3 + 2? It's 5. Write the 5 in the ones place of your answer.

13

+ 22

5

Now add the numbers in the tens place. What is 1 + 2? It's 3. Write the 3 in the tens place of your answer.

13

+ 22

35

You've solved the problem! The answer to 13 + 22 is 35.