## BEATCALC:  Beat the Calculator!

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 From B. Lee Clay

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### Multiplying a repeating 3's number by 55

1. Choose a repeating 3's number (333, etc.)

2. Multiply it by 55.
3. The product is:
- first two digits are 18: 18
- next repeating digits are 3's, two fewer than
repeating 3's in the original number
- the last two digits are 15

#### Example:

1. If the first number is 33:
2. Multiply the number by 55.
3. The product is:
- first two digits are 18: 18
- next repeating digits are 3's, two fewer than
repeating 3's in the original number:
- the last two digits are 15: 15.
4. So 33 × 55 = 1815.

#### Example:

1. If the first number is 33333:
2. Multiply the number by 55.
3. The product is:
- first two digits are 18: 18
- next repeating digits are 3's, two fewer than
repeating 3's in the original number: 333
- the last two digits are 15: 15.
4. So 33333 × 55 = 1833315.

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