Printable column addition worksheet for practicing three-digit addition with 20 problems and coloring instructions.

Let’s solve each addition problem step by step. We’ll add the ones first, then the tens, then the hundreds — just like the worksheet says.

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1) 367 + 254
Ones: 7 + 4 = 11 → write 1, carry 1
Tens: 6 + 5 = 11, plus 1 carried = 12 → write 2, carry 1
Hundreds: 3 + 2 = 5, plus 1 carried = 6
→ 621

2) 278 + 153
Ones: 8 + 3 = 11 → write 1, carry 1
Tens: 7 + 5 = 12, plus 1 = 13 → write 3, carry 1
Hundreds: 2 + 1 = 3, plus 1 = 4
→ 431

3) 683 + 275
Ones: 3 + 5 = 8
Tens: 8 + 7 = 15 → write 5, carry 1
Hundreds: 6 + 2 = 8, plus 1 = 9
→ 958

4) 526 + 249
Ones: 6 + 9 = 15 → write 5, carry 1
Tens: 2 + 4 = 6, plus 1 = 7
Hundreds: 5 + 2 = 7
→ 775

5) 486 + 395
Ones: 6 + 5 = 11 → write 1, carry 1
Tens: 8 + 9 = 17, plus 1 = 18 → write 8, carry 1
Hundreds: 4 + 3 = 7, plus 1 = 8
→ 881

6) 527 + 183
Ones: 7 + 3 = 10 → write 0, carry 1
Tens: 2 + 8 = 10, plus 1 = 11 → write 1, carry 1
Hundreds: 5 + 1 = 6, plus 1 = 7
→ 710

7) 724 + 135
Ones: 4 + 5 = 9
Tens: 2 + 3 = 5
Hundreds: 7 + 1 = 8
→ 859

8) 273 + 458
Ones: 3 + 8 = 11 → write 1, carry 1
Tens: 7 + 5 = 12, plus 1 = 13 → write 3, carry 1
Hundreds: 2 + 4 = 6, plus 1 = 7
→ 731

9) 634 + 97
Ones: 4 + 7 = 11 → write 1, carry 1
Tens: 3 + 9 = 12, plus 1 = 13 → write 3, carry 1
Hundreds: 6 + 0 = 6, plus 1 = 7
→ 731

10) 265 + 338
Ones: 5 + 8 = 13 → write 3, carry 1
Tens: 6 + 3 = 9, plus 1 = 10 → write 0, carry 1
Hundreds: 2 + 3 = 5, plus 1 = 6
→ 603

11) 537 + 86
Ones: 7 + 6 = 13 → write 3, carry 1
Tens: 3 + 8 = 11, plus 1 = 12 → write 2, carry 1
Hundreds: 5 + 0 = 5, plus 1 = 6
→ 623

12) 631 + 275
Ones: 1 + 5 = 6
Tens: 3 + 7 = 10 → write 0, carry 1
Hundreds: 6 + 2 = 8, plus 1 = 9
→ 906

13) 546 + 623
Ones: 6 + 3 = 9
Tens: 4 + 2 = 6
Hundreds: 5 + 6 = 11 → write 1, carry 1 to thousands? Wait — it’s 3-digit addition, but sum can be 4 digits.
Actually: 546 + 623 = 1169? Let’s check:
500 + 600 = 1100
40 + 20 = 60
6 + 3 = 9
Total: 1100 + 60 + 9 = 1169

But wait — the worksheet says “COLUMN ADDITION 3 DIGITS”, so maybe they expect only 3-digit answers? But mathematically, 546 + 623 is definitely 1169. Let’s keep going.

Actually, looking at other problems, some will exceed 999. So we’ll allow 4-digit answers.

→ 1169

14) 823 + 348
Ones: 3 + 8 = 11 → write 1, carry 1
Tens: 2 + 4 = 6, plus 1 = 7
Hundreds: 8 + 3 = 11 → write 1, carry 1 → so 1171
→ 1171

15) 684 + 425
Ones: 4 + 5 = 9
Tens: 8 + 2 = 10 → write 0, carry 1
Hundreds: 6 + 4 = 10, plus 1 = 11 → write 1, carry 1 → 1109
→ 1109

16) 473 + 596
Ones: 3 + 6 = 9
Tens: 7 + 9 = 16 → write 6, carry 1
Hundreds: 4 + 5 = 9, plus 1 = 10 → write 0, carry 1 → 1069
→ 1069

17) 764 + 582
Ones: 4 + 2 = 6
Tens: 6 + 8 = 14 → write 4, carry 1
Hundreds: 7 + 5 = 12, plus 1 = 13 → write 3, carry 1 → 1346
→ 1346

18) 846 + 677
Ones: 6 + 7 = 13 → write 3, carry 1
Tens: 4 + 7 = 11, plus 1 = 12 → write 2, carry 1
Hundreds: 8 + 6 = 14, plus 1 = 15 → write 5, carry 1 → 1523
→ 1523

19) 438 + 927
Ones: 8 + 7 = 15 → write 5, carry 1
Tens: 3 + 2 = 5, plus 1 = 6
Hundreds: 4 + 9 = 13 → write 3, carry 1 → 1365
→ 1365

20) 856 + 763
Ones: 6 + 3 = 9
Tens: 5 + 6 = 11 → write 1, carry 1
Hundreds: 8 + 7 = 15, plus 1 = 16 → write 6, carry 1 → 1619
→ 1619

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Now, let’s list all answers:

1) 621
2) 431
3) 958
4) 775
5) 881
6) 710
7) 859
8) 731
9) 731
10) 603
11) 623
12) 906
13) 1169
14) 1171
15) 1109
16) 1069
17) 1346
18) 1523
19) 1365
20) 1619

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Now, find the biggest and smallest answers.

Smallest: Look for the lowest number → 431 (problem 2)
Biggest: Look for the highest number → 1619 (problem 20)

So, shade problem 20’s answer green, and problem 2’s answer yellow.

Final Answer:
The biggest answer is 1619 (shade green), the smallest is 431 (shade yellow).