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From B. Lee Clay


 Squaring Numbers

 Multiplying Numbers

 Dividing Numbers

  1. any by 0.125
  2. 2 digits by 1 1/9
  3. 2 digits by 1 1/8
  4. 2 digits by 1 1/7
  5. 2 digits by 1 1/6
  6. 2 digits by 1 1/5
  7. 2 digits by 1 1/4
  8. 2 digits by 1 2/7
  9. 2 digits by 1 1/3
  10. 2 digits by 1 2/5
  11. 2 digits by 1 3/7
  12. 2 digits by 1 1/2
  13. 2 digits by 1 3/5
  14. 2 digits by 1 2/3
  15. 2 digits by 1 3/4
  16. 2 digits by 1 4/5
  17. 2 digits by 2 2/9
  18. 2 digits by 2 1/4
  19. 2 digits by 2 1/3
  20. 2,3 digits by 2 1/2
  21. 2 digits by 2 2/3
  22. 2 digits by 2 6/7
  23. 2 digits by 3 1/8
  24. 2,3 digits by 3 1/3
  25. 2 digits by 3 1/2
  26. 2 digits by 3 4/7
  27. 2 digits by 4 1/6
  28. 2 digits by 4 2/7
  29. 2 digits by 4 4/9
  30. 2 digits by 4 1/2
  31. 2 digits by 5
  32. 2 digits by 5 5/7
  33. 2 digits by 6 1/4
  34. 2 digits by 6 2/3
  35. 2 digits by 7 1/7
  36. 2 digits by 7 1/2
  37. 2 digits by 8 1/3
  38. 2 digits by 8 4/7
  39. 2 digits by 12 1/2
  40. 2 digits by 15
  41. 2,3 digits by 16 2/3
  42. 2,3 digits by 25
  43. 2,3 digits by 33 1/3
  44. 2,3 digits by 35
  45. 2 digits by 37 1/2
  46. 2 digits by 40
  47. 2 digits by 45
  48. 2 digits by 50
  49. 2 digits by 62 1/2
  50. 2 digits by 66 2/3
  51. 2,3 digits by 75
  52. 2 digits by 83 1/3
  53. 2 digits by 87 1/2
  54. 2 digits by 125
  55. 2 digits by 166 2/3
  56. 2 digits by 250
  57. 2,3 digits by 333 1/3
  58. 2 digits by 375
  59. 2 digits by 625
  60. 2 digits by 875
  61. 3 digits rep./37+41
  62. 6 digits rep. by 15873
  63. 6 digits rep. by 7, then 13
  64. 6 digits rep. by 13, then 11
  65. 6 digits rep. by 7,11,13, subtract 101
  66. 6 digits rep. by 37037 x 5
  67. mixed numbers by 2
  68. diff. of squares of 2 consec. 2-digit numbers
  69. diff. of squares of 2 different 2-digit numbers
  70. sqrt of squares of 2-digit numbers ending in 1
  71. sqrt of perfect squares ending in 5

 Adding Numbers

 Subtracting Numbers

 Finding Percents

Calculation
Practice Exercises

Full List



   Dividing mixed numbers by 2

  1. Select a mixed number (a whole number and a fraction).
  2. If the whole number is even, divide by 2 -
    this is the whole number of the answer.
    • The numerator of the fraction stays the same;
      multiply the denominator by 2.
  3. If the whole number is odd, subtract 1 and divide by 2 -
    this is the whole number of the answer.
    • Add the numerator and the denominator of the fraction - this will be the new numerator of the fraction;
    • Multiply the denominator by 2.

   Even whole number example:

  1. If the first number selected is 8 3/4:
  2. Divide the whole number (8) by 2: 8/2 = 4 (whole number)
  3. Use the same numerator: 3
  4. Multiply the denominator by 2: 4 × 2 = 8 (denominator)
  5. So 8 3/4 divided by 2 = 4 3/8.

   Odd whole number example:

  1. If the first number selected is 13 2/5:
  2. Subtract 1 from the whole number and divide by 2:
    13 - 1 = 12, 12/2 = 6.
  3. Add the numerator and the denominator: 2 + 5 = 7.
    This is the numerator of the fraction.
  4. Multiply the denominator by 2: 5 × 2 = 10.
  5. So 13 2/5 divided by 2 = 6 7/10.


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23 September 1996
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