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Doubling and Halving Mental Maths Worksheet

Mental maths lesson 9: Doubling and halving · Set 499 · 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 39 =
  2. 2.Double 49 =
  3. 3.Double 42 =
  4. 4.Half of 166 =
  5. 5.Half of 84 =
  6. 6.Half of 86 =
  7. 7.Half of 150 =
  8. 8.Double 28 =
  9. 9.Half of 100 =
  10. 10.Half of 68 =
  11. 11.Double 41 =
  12. 12.Half of 28 =
  13. 13.Half of 102 =
  14. 14.Double 32 =
  15. 15.Half of 90 =
  16. 16.Double 89 =
  17. 17.Half of 124 =
  18. 18.Double 21 =
  19. 19.Double 29 =
  20. 20.Half of 50 =
  21. 21.Double 84 =
  22. 22.Double 54 =
  23. 23.Double 65 =
  24. 24.Double 62 =
  25. 25.Half of 36 =
  26. 26.Half of 178 =
  27. 27.Half of 174 =
  28. 28.Half of 26 =
  29. 29.Double 47 =
  30. 30.Double 57 =
  31. 31.Double 16 =
  32. 32.Half of 92 =
  33. 33.Half of 96 =
  34. 34.Double 74 =
  35. 35.Double 26 =
  36. 36.Double 76 =
  37. 37.Half of 42 =
  38. 38.Double 23 =
  39. 39.Half of 74 =
  40. 40.Double 91 =

Answer key

  1. 78
  2. 98
  3. 84
  4. 83
  5. 42
  6. 43
  7. 75
  8. 56
  9. 50
  10. 34
  11. 82
  12. 14
  13. 51
  14. 64
  15. 45
  16. 178
  17. 62
  18. 42
  19. 58
  20. 25
  21. 168
  22. 108
  23. 130
  24. 124
  25. 18
  26. 89
  27. 87
  28. 13
  29. 94
  30. 114
  31. 32
  32. 46
  33. 48
  34. 148
  35. 52
  36. 152
  37. 21
  38. 46
  39. 37
  40. 182

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