How to Add Two Three-Digit Numbers Without Regrouping

Adding two three-digit numbers without regrouping is an important skill for students to learn as it lays the foundation for more complex addition problems. In this post, we’ll walk you through the process of adding numbers step by step, using clear and simple examples. Whether you’re working with school assignments or practicing at home, this guide will help you master the art of adding three-digit numbers quickly and easily!

What Does “Without Regrouping” Mean?

Before we dive into the examples, let’s first explain what “without regrouping” means. When you add numbers, sometimes the sum of a column (like the ones, tens, or hundreds) can be greater than 9. This means you need to “regroup” or carry over the extra value to the next column. However, when we add without regrouping, the sum in each column will always be less than 10, so no carrying over is needed.

Steps for Adding Two Three-Digit Numbers Without Regrouping

Let’s break down the steps for adding two three-digit numbers without regrouping:

1. Write the numbers vertically: Place the numbers one under the other, aligning the ones, tens, and hundreds columns.Example:
   234 + 453 = ?
2. Start from the rightmost column (ones): Add the digits in the ones place. If the sum is less than 10, write the sum in the ones place of the answer.In our example, 4 + 3 = 7. So, we write 7 in the ones column.
3. Move to the tens column: Now, add the digits in the tens column. Again, if the sum is less than 10, write the sum in the tens place of the answer.In our example, 3 + 5 = 8. So, we write 8 in the tens column.
4. Add the hundreds column: Finally, add the digits in the hundreds place. If the sum is less than 10, write the sum in the hundreds place of the answer.In our example, 2 + 4 = 6. So, we write 6 in the hundreds column.
5. Write the final sum: Now, you can combine all the sums from the ones, tens, and hundreds columns. The final sum is the number that you get from these three columns.So, 234 + 453 = 687.

Example 1: Adding 234 and 453

Let’s take a closer look at this addition problem:

234 + 453 =?

---

 

• In the ones place: 4 + 3 = 7
• In the tens place: 3 + 5 = 8
• In the hundreds place: 2 + 4 = 6

So, the sum of 234 + 453 is 687. No regrouping was needed because all the sums were less than 10 in each column.

Example 2: Adding 512 and 376

Now let’s try another example:

512 + 376 = ?

---

 

• In the ones place: 2 + 6 = 8
• In the tens place: 1 + 7 = 8
• In the hundreds place: 5 + 3 = 8

So, the sum of 512 + 376 is 888. Again, no regrouping was necessary!

Why is Adding Without Regrouping Important?

Adding without regrouping is a vital skill that students use throughout their math education. It helps develop number sense, which is essential for understanding how numbers work together. When students master simple addition problems like these, they gain the confidence to move on to more complex problems that require regrouping.

Practice Problems for You

Here are some practice problems for you to try on your own. Remember, no regrouping is required in these problems!
1) Add these numbers:

2) Add these numbers:

3) Add these numbers:

4) Add these numbers:

5) Add these numbers:

6) Add these numbers:

7) Add these numbers:

8) Add these numbers:

9) Add these numbers:

10) Add these numbers:

Answers:
1) 559
2) 787
3) 942
4) 779
5) 992
6) 935
7) 728
8) 249
9) 440
10) 689