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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 a 2-digit number by 4 2/7

  1. Select a 2-digit number.
  2. Multiply it by 7.
  3. Divide the product by 3.
  4. Move the decimal point 1 place to the left.

   Example:

  1. The number chosen to divide by 4 2/7 is 62.
  2. Multiply by 7: 7 × 62 = 420 + 14 = 434
  3. Divide by 3: 434/3 = 144 2/3
  4. Move the decimal point 1 place to the left: 14.4 2/3
  5. So 62 divided by 4 2/7 = 14.4 2/3.

   See the pattern?

  1. The number chosen to divide by 4 2/7 is 81.
  2. Multiply by 7: 7 × 81 = 567
  3. Divide by 3: 567/3 = 189
  4. Move the decimal point 1 place to the left: 18.9
  5. So 81 divided by 4 2/7 = 18.9.
People who use calculators will get answers with long decimals. Your answers will be exact.


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