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Doubling and Halving Mental Maths Worksheet

Mental maths lesson 9: Doubling and halving · Set 321 · 40 questions
TalentJR

How to do it in your head (Split, then double or halve): To double: split into tens and ones, double both, add. To halve: split into an even number of tens and the rest (156 = 140 + 16). Halve both parts and add.

NameDateTime takenScore ___ / 40
  1. 1.Double 99 =
  2. 2.Half of 142 =
  3. 3.Double 71 =
  4. 4.Half of 128 =
  5. 5.Double 21 =
  6. 6.Double 36 =
  7. 7.Double 73 =
  8. 8.Half of 96 =
  9. 9.Double 51 =
  10. 10.Half of 64 =
  11. 11.Double 53 =
  12. 12.Double 18 =
  13. 13.Double 16 =
  14. 14.Double 77 =
  15. 15.Double 57 =
  16. 16.Half of 58 =
  17. 17.Half of 46 =
  18. 18.Double 35 =
  19. 19.Double 63 =
  20. 20.Double 98 =
  21. 21.Double 17 =
  22. 22.Double 42 =
  23. 23.Double 26 =
  24. 24.Half of 48 =
  25. 25.Double 92 =
  26. 26.Double 79 =
  27. 27.Half of 106 =
  28. 28.Half of 116 =
  29. 29.Double 44 =
  30. 30.Double 81 =
  31. 31.Half of 166 =
  32. 32.Half of 192 =
  33. 33.Half of 114 =
  34. 34.Half of 180 =
  35. 35.Double 54 =
  36. 36.Double 41 =
  37. 37.Double 91 =
  38. 38.Half of 144 =
  39. 39.Double 95 =
  40. 40.Half of 124 =

Answer key

  1. 198
  2. 71
  3. 142
  4. 64
  5. 42
  6. 72
  7. 146
  8. 48
  9. 102
  10. 32
  11. 106
  12. 36
  13. 32
  14. 154
  15. 114
  16. 29
  17. 23
  18. 70
  19. 126
  20. 196
  21. 34
  22. 84
  23. 52
  24. 24
  25. 184
  26. 158
  27. 53
  28. 58
  29. 88
  30. 162
  31. 83
  32. 96
  33. 57
  34. 90
  35. 108
  36. 82
  37. 182
  38. 72
  39. 190
  40. 62

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