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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   Multiplying a 2-digit number by 250

  1. Select a 2-digit number.
  2. Divide the number by 4.
  3. Move the decimal point 3 places to the right (add three zeros).

   Example:

  1. The 2-digit number chosen to multiply by 250 is 96.
  2. Divide by 4: 96/4 = 24
  3. Add three zeros: 24000
  4. So 96 x 250 = 24,000.

   See the pattern?

  1. The 2-digit number chosen to multiply by 250 is 37.
  2. Divide by 4: 37/4 = 9.25
  3. Move the decimal point 3 places to the right: 9250
  4. So 37 x 250 = 9,250.


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13 December 1999
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