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Grade 3 Adding in Your Head Worksheets

Add two numbers without writing anything down, first without carrying and then with.

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Mental Maths · Grade 3

Grade
Topic
SkillEach skill is a different kind of question, with its own levels.
Level
Questions
30

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Grade 3 · 2 pages · A4

Mental Maths Practice

Grade 3 • Adding in Your Head • Sums that carry
Name:Date:

Answer as fast as you can, in your head. No calculator.

  1. 1) 169 + 21 =
  2. 2) 135 + 35 =
  3. 3) 177 + 19 =
  1. 4) 163 + 29 =
  2. 5) 178 + 16 =
  3. 6) 144 + 46 =
  1. 7) 143 + 29 =
  2. 8) 109 + 53 =
  3. 9) 172 + 18 =
  1. 10) 122 + 28 =
  2. 11) 162 + 18 =
  3. 12) 101 + 29 =
  1. 13) 137 + 17 =
  2. 14) 159 + 39 =
  3. 15) 122 + 18 =
  1. 16) 126 + 46 =
  2. 17) 124 + 16 =
  3. 18) 116 + 16 =
  1. 19) 151 + 29 =
  2. 20) 109 + 37 =
  3. 21) 114 + 29 =
  1. 22) 154 + 19 =
  2. 23) 149 + 46 =
  3. 24) 107 + 69 =
  1. 25) 177 + 15 =
  2. 26) 147 + 14 =
  3. 27) 168 + 25 =
  1. 28) 143 + 27 =
  2. 29) 139 + 56 =
  3. 30) 115 + 76 =
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Page 1 of 2

Answer Key

  1. 1. 190
  2. 2. 170
  3. 3. 196
  4. 4. 192
  1. 5. 194
  2. 6. 190
  3. 7. 172
  4. 8. 162
  1. 9. 190
  2. 10. 150
  3. 11. 180
  4. 12. 130
  1. 13. 154
  2. 14. 198
  3. 15. 140
  4. 16. 172
  1. 17. 140
  2. 18. 132
  3. 19. 180
  4. 20. 146
  1. 21. 143
  2. 22. 173
  3. 23. 195
  4. 24. 176
  1. 25. 192
  2. 26. 161
  3. 27. 193
  4. 28. 170
  1. 29. 195
  2. 30. 191
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Page 2 of 2

What each level generates

Grade 3 adding in your head — the exact skill behind each difficulty setting, straight from the generator.

  1. Level 1Sums with no carrying
  2. Level 2Sums that carry
  3. Level 3Add three numbers

Grade levels follow the progression common to most English-language curricula — not one specific national curriculum. Every level shows exactly what it generates, so you can check the fit with your own program. See the full scope & sequence →

More Grade 3 mental maths skills

Each one generates a different kind of question, with its own three levels and answer key.

Frequently asked questions

▸What is mental maths for Grade 3?

Working out addition, subtraction and multiplication in the head. Each skill has a sheet of its own, and the Mixed Chains sheet rotates the three operations so a child practises choosing a strategy, not just repeating one.

▸Should my child know all the times tables by Grade 3?

Most Grade 3 programmes aim for the tables up to 10 by the end of the year, with 11 and 12 following. Times Table Facts keeps to the tables up to 10 at every Grade 3 level — straight recall, then the missing factor, then three factors — and the Grade 4 sheets extend to 12.

▸Why practise mixed operations as well as one skill at a time?

Because switching is the skill that transfers. A single-operation page lets a child answer on autopilot; the Mixed Chains sheet forces them to read the symbol and pick a method, which is what any real problem will demand of them. Use both — one skill at a time to build the facts, mixed chains to prove they hold.

▸What does the Mixed Chains sheet generate?

Chains that mix operations: 54 + 32 − 75 at the first level, 7 × 6 + 24 at the second, and four numbers in a row at the third. The multiplication always comes first so the answer is never ambiguous, and every result stays a positive whole number.