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From B. Lee Clay


 Squaring Numbers

  1. beginning with 1
  2. beginning with 5
  3. beginning with 9
  4. ending in 1
  5. ending in 2
  6. ending in 3
  7. ending in 4
  8. ending in 5
  9. ending in 6
  10. ending in 7
  11. ending in 8
  12. ending in 9
  13. made up of 1's
  14. made up of 3's
  15. made up of 6's
  16. made up of 9's
  17. in the 20's
  18. in the 30's
  19. in the 40's
  20. in the 50's
  21. in the 60's
  22. in the 70's
  23. in the 80's
  24. in the 100's
  25. in the 200's
  26. in the 300's
  27. in the 400's
  28. in the 500's
  29. in the 600's
  30. in the 700's
  31. between 800-810
  32. in the 900's
  33. between 1000-1100
  34. between 2000-2099
  35. between 3000-3099
  36. between 4000-4099
  37. between 5000-5099
  38. between 6000-6099
  39. between 7000-7099
  40. 3's and final 1
  41. 3's and final 2
  42. 3's and final 4
  43. 3's and final 5
  44. 3's and final 6
  45. 3's and final 7
  46. 3's and final 8
  47. 3's and final 9
  48. 6's and final 1
  49. 6's and final 2
  50. 6's and final 3
  51. 6's and final 4
  52. 6's and final 5
  53. 6's and final 7
  54. 6's and final 8
  55. 6's and final 9
  56. 9's and final 1
  57. 9's and final 2
  58. 9's and final 3
  59. 9's and final 4
  60. 9's and final 5
  61. 9's and final 6
  62. 9's and final 7
  63. 9's and final 8
  64. 1 and repeating 3's
  65. 1 and repeating 6's
  66. 1 and repeating 9's
  67. 2 and repeating 3's
  68. 2 and repeating 6's
  69. 2 and repeating 9's
  70. 3 and repeating 6's
  71. 3 and repeating 9's
  72. 4 and repeating 3's
  73. 4 and repeating 6's
  74. 4 and repeating 9's
  75. 5 and repeating 3's
  76. 5 and repeating 6's
  77. 5 and repeating 9's
  78. 6 and repeating 3's
  79. 6 and repeating 9's
  80. 7 and repeating 3's
  81. 7 and repeating 6's
  82. 7 and repeating 9's
  83. 8 and repeating 3's
  84. 8 and repeating 9's
  85. 9 and repeating 3's
  86. 9 and repeating 6's
  87. 6-digits repeating
  88. 2 rep./sq. of 1 digit

 Multiplying Numbers

 Dividing Numbers

 Adding Numbers

 Subtracting Numbers

 Finding Percents

Calculation
Practice Exercises

Full List



    Squaring numbers between 2000 and 2099

  1. Choose a number between 2000 and 2099. (Start with numbers below 2025 to begin with, then graduate to larger numbers.)
  2. The first two digits are: 4 0 _ _ _ _ _
  3. The next two digits are 4 times the last two digits:
    4 0 X X _ _ _
  4. For the last three digits, square the last two digits in the number chosen (insert zeros when needed):
    4 0 _ _ X X X

   Example:

  1. If the number to be squared is 2003:
  2. The first two digits are: 4 0 _ _ _ _ _
  3. The next two digits are 4 times the last two:
    4 × 3 = 12: _ _ 1 2 _ _ _
  4. For the last three digits, square the last two:
    3 × 3 = 9: _ _ _ _ 0 0 9
  5. So 2003 × 2003 = 4,012,009.

   See the pattern?

    For larger numbers, reverse the order:

  1. If the number to be squared is 2025:
  2. For the last three digits, square the last two:
    25 × 25 = 625: _ _ _ _ 6 2 5
  3. The middle two digits are 4 times the last two (keep the carry):
    4 × 25 = 100 (keep carry of 1): _ _ 0 0 _ _ _
  4. The first two digits are 40 + the carry:
    40 + 1 = 41: 4 1 _ _ _ _ _
  5. So 2025 × 2025 = 4,100,625.


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8 November 1999
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