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Addition 3 Digit Numbers - Printable Mathematics Worksheets - Wayground

Addition 3 Digit Numbers

26 questions

3rd - 3rd Grade

Mathematics

Addition 3 Digit Numbers is a Grade 3 mathematics worksheet that builds place-value understanding and three-digit addition fluency through 26 multiple-choice questions. Students translate among standard form, expanded form, and place-value descriptions; identify hundreds, tens, and ones; and solve three-digit addition equations, including sums greater than 1,000. The questions use examples such as 326 + 123, 401 + 411, and 567 + 996 to connect expanded-form reasoning with accurate computation. This free printable worksheet is useful for independent practice, guided review, or a quick check of students’ understanding of representing and adding three-digit numbers. A complete answer key is included so teachers can review common place-value and addition errors efficiently.

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Addition 3 Digit Numbers

Total questions: 26

Name
Class
Date
1.

How would I use expanded form to solve 326+123?

a)

300+2+6

+100+2+3

=400+4+9=449

b)

300+20+6

+100+20+3

=400+40+9=449

c)

3+2+6

+1+2+3

=4+4+9=449

d)

449

2.

How would you solve 401+411 with expanded form?

a)

401

+411

=812

b)

400+1

+400+1+1

=800+1+1=812

c)

400+0+1

+400+1+1

=8+1+1=812

d)

400+0+1

+400+10+1

=800+10+1=812

3.
Write the number in number form. 
a)
258
b)
377
c)
358
d)
659
4.
300+60+8=
a)
386
b)
123
c)
308
d)
368
5.
901 in expanded form
a)
900+0+1
b)
90+0
c)
9+1
d)
4+5
6.
How many hundreds in 980?
a)
9
b)
8
c)
0
d)
90
7.
What is the standard form for 3 hundreds 4 tens and 3 ones?
a)
3431
b)
343
c)
3430
d)
34
8.
Turn 537 into Expanded form
a)
50 + 30 + 7
b)
5 + 3 + 7
c)
500 +30 + 7
d)
7 +530 + 30
9.
  604
 + 207 = 
a)
705
b)
811
c)
712
d)
615
10.
509
+ 372 =
a)
991
b)
756
c)
881
d)
893
11.
735
+ 543 = 
a)
1,278
b)
1,379
c)
2,259
d)
2,279
12.
567
+ 996 = 
a)
1,463
b)
1,563 
c)
1,542
d)
1,462
13.
556
+ 525 = 
a)
1,092
b)
2,081
c)
2,092
d)
1,081
14.
215
+ 775 = 
a)
1,091
b)
990
c)
891
d)
982
15.
What is 147 in expanded form?
a)
1+4+7
b)
100+4+7
c)
100+40+7
16.
What is 760 in expanded form?
a)
700+60+0
b)
7+6+0
c)
70+6+0
17.
What is 400+50+2 in standard form?
a)
400502
b)
452
c)
11
18.
Which is another way to write the number?
one thousand, forty-two
a)
1,000 + 40 + 2
b)
1,000 + 400 + 20
c)
100 + 40 + 2
19.
Write the expanded form of 235.
a)
200+30+5
b)
200+50+3
c)
300+20+5
d)
500+30+2
20.

Write the expanded form of 421.

a)

400+10+2

b)

400+20+1

c)

200+40+1

d)

100+20+4

21.
What is 100 + 50 + 7 =? 
a)
157
b)
571
c)
175
d)
100507
22.
what is 269 in expanded form? 
a)
200+60+8
b)
200+70+9
c)
200+60+9
d)
600+20+9
23.
What number is this 300+ 90+3
a)
983
b)
393
c)
933
d)
339
24.

353

+210

________

________

a)

573

b)

473

c)

563

d)

543

25.

436

+160

________

________

a)

696

b)

896

c)

546

d)

596

26.

220

+219 .

________

________

a)

439

b)

449

c)

539

d)

549

Answer Key

Addition 3 Digit Numbers

Total questions: 26

1.
b)

300+20+6

+100+20+3

=400+40+9=449

2.
d)

400+0+1

+400+10+1

=800+10+1=812

3.
b) 377
4.
d) 368
5.
a) 900+0+1
6.
a) 9
7.
b) 343
8.
c) 500 +30 + 7
9.
b) 811
10.
c) 881
11.
a) 1,278
12.
b) 1,563 
13.
d) 1,081
14.
b) 990
15.
c) 100+40+7
16.
a) 700+60+0
17.
b) 452
18.
a) 1,000 + 40 + 2
19.
a) 200+30+5
20.
b)

400+20+1

21.
a) 157
22.
c) 200+60+9
23.
b) 393
24.
c)

563

25.
d)

596

26.
a)

439

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FAQs

What does the Addition 3 Digit Numbers worksheet cover?

This Grade 3 mathematics worksheet uses 26 multiple-choice questions to practise writing three-digit numbers in standard and expanded form, identifying hundreds, tens, and ones, and adding three-digit numbers. Students use place-value representations such as 300 + 20 + 6 before solving addition problems, helping them connect the structure of a number to accurate computation.

How can I use this worksheet to teach three-digit addition with expanded form?

Begin by modeling one expanded-form item, such as decomposing 326 and 123 into hundreds, tens, and ones, then combine the place values to find the sum. Have students explain why 400 + 40 + 9 represents 449 before they work through the multiple-choice questions, and use the later addition items to check whether they can apply the same place-value reasoning to larger sums.

What mistakes should I watch for when students complete this worksheet?

Students may confuse a digit with its place value, such as reading 537 as 50 + 30 + 7 instead of 500 + 30 + 7, or omit a zero when expanding numbers such as 901 and 604. In the addition items, watch for errors in aligning hundreds, tens, and ones or in carrying to create four-digit totals, such as the sum of 567 + 996.

How do I assign and grade this Addition 3 Digit Numbers worksheet?

The worksheet is available as a printable PDF and as a digital quiz on Wayground, and it includes a complete answer key for checking the 26 multiple-choice items. For printable submissions, you can scan student work with the Wayground for Teachers app to streamline grading.

How can I differentiate this three-digit addition worksheet for my students?

In the worksheet’s Advanced Settings, adjust font spacing or choose a larger font size to make the place-value expressions, addition equations, and multiple-choice options easier to read. You can also enable a dyslexia-friendly font or translate the worksheet into another language when those file-level changes support access to the questions.

Where can I find more worksheets like this on Wayground?

Wayground offers a comprehensive collection of free printable worksheets and practice problems across all subjects, with downloadable PDFs and answer keys to help students master essential skills and concepts. Browse more resources at https://wayground.com/en-us/worksheets.

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