BEATCALC:  Beat the Calculator!

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Back to Calculation Tips & Tricks
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From the BEATCALC mailing list:
a weekly service from B. Lee Clay, archived here by the Math Forum.
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   Dividing a 2-digit number by 2 2/3

  1. Select a 2-digit number.
  2. Multiply by 3.
  3. Divide by 8.

   Example:

  1. The 2-digit number chosen to divide by 2 2/3 is 32.
  2. Multiply by 3: 3 x 32 = 96
  3. Divide by 8: 96/8 = 12
  4. So 32 divided by 2 2/3 = 12.

   See the pattern?

  1. The 2-digit number chosen to divide by 2 2/3 is 61.
  2. Multiply by 3: 3 x 61 = 183
  3. Divide by 8: 183/8 = 22 7/8
  4. So 61 divided by 2 2/3 = 22 7/8.

Using this method, your answers will be exact. Those using calculators will only get approximations.


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17 January 2000
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