BEATCALC:  Beat the Calculator!

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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 45

  1. Select a 2-digit number.
  2. Divide by 5.
  3. Divide the resulting number by 9.

   Example:

  1. If the number chosen to divide by 45 is 32:
  2. Divide by 5: 32/5 = 6.4
  3. Divide the result by 9: 6.4/9 = .71 1/9
  4. So 32 divided by 45 = .71 1/9.

   See the pattern?

  1. If the number chosen to divide by 45 is 61:
  2. Divide by 5: 61/5 = 12.2
  3. Divide the result by 9: 12.2/9 = 1.35 5/9
  4. So 61 divided by 45 = 1.35 5/9.


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17 July 2000
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