## BEATCALC:  Beat the Calculator!

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 From B. Lee Clay

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### Multiplying a 2-digit number by 103               and adding 12

1. Select a 2-digit number less than 34.
2. The result is:
Leading two digits are the original number selected.
Last two digits are three times the selected number.
Add 12. (To disguise selected number's relation to product)

#### Example:

1. Number selected is 21.
103 × 21 + 12
Leading two digits are the original number: 21 _ _.
Last two digits are three times the selected number: _ _ 63.
So 103 × 21 = 2163.
Add 12: 2163 + 12 = 2175.

#### Example:

1. Number selected is 32.
103 × 32 + 12
Leading two digits are the original number: 32 _ _.
Last two digits are three times the selected number: _ _ 96.
So 103 × 32 = 3296.
Add 12: 3296 + 12 = 3308.

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17 April 2007
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