Worked Example 1
Adding With Regrouping
3,478 + 2,945
- 1Ones: 8 + 5 = 13. Write 3, regroup 1 ten.
- 2Tens: 7 + 4 + 1 = 12. Write 2, regroup 1 hundred.
- 3Hundreds: 4 + 9 + 1 = 14. Write 4, regroup 1 thousand.
- 4Thousands: 3 + 2 + 1 = 6
Answer: 6,423
Florida Grade 3 Math · Number Sense and Operations
MA.3.NSO.2.1: Adding and Subtracting Multi-Digit Numbers
What this Grade 3 benchmark means, worked examples, common mistakes, and a free printable worksheet.
Created by a Florida mom · Published by Tropical Learning LLC
What Is Benchmark MA.3.NSO.2.1?
Grade 3 students add and subtract multi-digit whole numbers with procedural fluency, which means accurately, efficiently, and flexibly. This includes the standard algorithm, where numbers are lined up by place value and regrouped as needed.
Regrouping across zeros (like 5,003 − 1,867) is one of the hardest parts and worth extra practice.
Official benchmarkAdd and subtract multi-digit whole numbers including using a standard algorithm with procedural fluency.
On the FAST test: part of the Grade 3 reporting category Number Sense and Additive Reasoning, which is about 23–29% of the test.
Worked Examples
Worked Example 2
Subtracting Across Zeros
5,003 − 1,867
- 1You need more ones, but there are no tens or hundreds to trade.
- 2Regroup 5,003 as 4 thousands, 9 hundreds, 9 tens, and 13 ones.
- 3Ones: 13 − 7 = 6. Tens: 9 − 6 = 3. Hundreds: 9 − 8 = 1. Thousands: 4 − 1 = 3.
Answer: 3,136
Common Mistakes to Watch For
Forgetting the regrouped 1
Wrong:468 + 357 = 715
8 + 7 = 15, so write 5 and regroup 1. 6 + 5 + 1 = 12, so write 2 and regroup 1. 4 + 3 + 1 = 8. The sum is 825.
Subtracting the smaller digit from the larger one in each place
Wrong:702 − 158 = 656
You can't take 8 ones from 2 ones, so regroup: 702 is 6 hundreds, 9 tens, 12 ones. 12 − 8 = 4, 9 − 5 = 4, 6 − 1 = 5. The difference is 544.
Helpful Math Tip
Check subtraction by adding: the answer plus the number you subtracted should equal the number you started with.
Related Grade 3 Skills
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Start Practicing FreeIndependent Educational Platform. FastChomp is published by Tropical Learning LLC and is not affiliated with, sponsored by, or endorsed by the Florida Department of Education. FAST and Star assessment names are referenced for informational purposes only. FastChomp practice questions are original educational materials, not official Florida FAST assessment questions.