Addition to 100
On this page children practise revising and extending addition to 100 with a focus on mental strategies and checking with inverse tasks. Start with the short method and the examples, then use the online practice or print a worksheet with answers.
How to solve this
- Adding numbers within 100 in grade 3 focuses on fluency — aim to recall or calculate instantly.
- Use mental strategies: split into tens and ones, bridge through a round ten, or use known doubles.
- Check with a quick estimate: round both numbers to the nearest ten and verify the answer is close.
Examples
47 + 36 = ?
83
58 + 24 = ?
82
39 + 45 = ?
84
Practice problems with answers
Solve these problems on paper or out loud, then check the answer key. The online practice and the printable worksheet give a new set every time.
- 82 + 15 = ___
- 67 + 21 = ___
- 79 + 20 = ___
- 64 + 33 = ___
- 50 + 15 = ___
- 57 + 29 = ___
- 77 + 20 = ___
- 32 + 47 = ___
Show answers
- 97
- 88
- 99
- 97
- 65
- 86
- 97
- 79