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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   Multiplying a 2-digit number by 2 2/3

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

   Example:

  1. The 2-digit number chosen to multiply by 2 2/3 is 24.
  2. Multiply by 8: 8 x 24 = 160 + 32 = 192.
  3. Divide by 3: 192/3 = 64.
  4. So 24 x 2 2/3 = 64.

   See the pattern?

  1. The 2-digit number chosen to multiply by 2 2/3 is 68.
  2. Multiply by 8: 8 x 68 = 480 + 64 = 544.
  3. Divide by 3: 544/3 = 181 1/3.
  4. So 68 x 2 2/3 = 181 1/3.


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