How to Add Two-Digit Numbers With Regrouping

      Two-digit numbers are the numbers from 10 to 99.

In the last lesson, you learned how to add two-digit numbers.

Let's review with an example.

33 + 21 = ?

First, we write the numbers in column form.

Tip: The Ones go on the right (👉).

Start by adding the Ones column.

Finally, add the Tens column. 

Addition With Regrouping

Sometimes the digits in one column can add up to more than 9!

Take a look:

16 + 78 = ?

Let's write this in column form.

First, we add the Ones.

We get 14!

But we can't write two digits in one column. 🙀

We need to regroup! 👍

      Regrouping is when you take 10 Ones and turn them into 1 Tens!

Tip: Regrouping is also called "carrying the 1 over."

Finally, we add the Tens, including the carry over.

Our answer is 94.

Great work!

Last Example

29 + 35 = ?

What's the first step? 

Yes, column form!

When we add the Ones, we get 14. 

"Carry the 1 over" to the Tens column.

Now, we can add the Tens, including the carry over.

Nice job!

Now, it's time to practice. You can do it! 😺