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 repeating 6-digit number by 37037,
                     multiplying by 5

  1. Select a 6-digit number repeating number.
  2. Repeat these digits to make a 6-digit number.
  3. Multiply a single digit by 3, then by 5.

   Example:

  1. If the 6-digit repeating number selected is 333333:
  2. Multiply 3 x 3: 9
  3. Multiply 9 x 5: 45
  4. So 333333 divided by 37037 and multiplied by 5 is 45.

   See the pattern?

You can expand this exercise by using a different number in the final step.

   Example: multiply by 4:

  1. If the 6-digit repeating number selected is 555555:
  2. Multiply 3 x 5: 15.
  3. Multiply 15 x 4: 60
  4. So 555555 divided by 37037 and multiplied by 4 is 60.

By changing the last step you can generate many extensions of this exercise. Be inventive and create some impressive calculations.


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5 August 1996
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