3-Digit Addition Worksheets

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In mathematical addition, the higher the base numbers being added, the more frequently students might have to regroup or carry; however, this concept may be difficult for young students to grasp without a visual representation to help them.

While the concept of regrouping may seem complex, it's best understood through practice. Use the following three-digit addition with regrouping worksheets to help guide your students or child through learning how to add large numbers. Each slide offers a free printable worksheet followed by an identical worksheet listing the answers for ease of grading.

Worksheet No. 1: 3-Digit Addition with Regrouping

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By second grade, students should be able to complete worksheets such as this one, which require them to use regrouping to calculate sums of large numbers. If students are struggling, give them visual aids like counters or number lines to calculate each decimal point value.

Worksheet No. 2: 3-Digit Addition with Regrouping

In this worksheet, students continue to practice three-digit addition with regrouping. Encourage students to write on the printed worksheets and remember to "carry the one" each time it occurs by writing a small "1" above the next decimal value then writing the total (minus 10) in the decimal place that was being calculated.

Worksheet No. 3: 3-Digit Addition with Regrouping

By the time students get to three-digit addition, they typically have already developed a fundamental understanding of the sum, which they reach by adding single-digit numbers. They should be able to quickly understand how to add larger numbers if they tackle addition problems one column at a time by adding each decimal place individually and carrying the one when the sum is greater than 10.

Worksheet No. 4: 3-Digit Addition with Regrouping

For this worksheet, students will tackle regrouping problems, such as 742 plus 804. Explain that in this problem, no regrouping is required for the ones column (2 + 4 = 6) or for the tens column (4 = 0 = 4). But they will need to regroup for the hundreds column (7 + 8). Explain that for this part of the problem, students would add the seven and eight, yielding 15. They would place the "5" in the hundreds column and carry the "1" to the thousands column. The answer to the full problem, then, is 1,546.

Worksheet No. 5: 3-Digit Addition with Regrouping

If students are still struggling, explain that with regrouping, each decimal place can only go up to 10. This is called "place value," which means that the value of the digit is based on its position. If adding the two numbers in the same decimal place results in a number greater than 10, students need to write the number in the ones place then carry the "1" into the tens place. If the result of adding both tens place values is greater than 10, then students need to carry that "1" to the hundreds place.

Worksheet No. 6: 3-Digit Addition with Regrouping

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Many of the problems on these worksheets explore questions that produce four-digit sums and oftentimes require students to regroup multiple times per addition. These can be challenging for beginner mathematicians, so it's best to walk students through the core concepts of three-digit addition thoroughly before challenging them with these more difficult worksheets.

Worksheet No. 7: 3-Digit Addition with Regrouping

Tell students that on this and the following worksheets each decimal place after the three-digit hundreds place operates in exactly the same manner as in the preceding printables. By the time students reach the end of the second grade, they should be able to add more than two three-digit numbers by following the same regrouping rules.

Worksheet No. 8: 3-Digit Addition with Regrouping

On this worksheet, students will add both two- and three-digit numbers. Sometimes the two-digit number will be the top number in the problem, also called the augend. In other cases, the two-digit number, also known as the addend, is on the bottom row of the problem. For either case, the regrouping rules discussed previously still apply.

Worksheet No. 9: 3-Digit Addition with Regrouping

In this worksheet, students will add several numbers that include "0" as one of the digits. Sometimes second-graders have difficulty with the concept of zero. If this is the case, explain that any number added to zero equals that number. For example, "9 +0" still equals zero, and "3 + 0" equals zero. Do a problem or two that contain a zero on the board if needed to demonstrate.

Worksheet No. 10: 3-Digit Addition with Regrouping

Students' understanding of the concept of regrouping will greatly impact their aptitude in the field of advanced mathematics they will have to study in junior high and high school, so it's important to ensure that your students fully grasp the concept before continuing to multiplication and division lessons. Repeat one or more of these worksheets if students need more practice in regrouping.