## BEATCALC:  Beat the Calculator!

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 From B. Lee Clay

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### Multiplying a repeating 4's number by 99

• Choose a repeating 4's number (444, etc.)
• Multiply it by 99
• The product is:
- first two digits are 43
- next digits are repeating 4's - two fewer than the repeating 4's in the original number
- last two digits are 56.

#### Example:

1. If the first number is 4444:
2. Multiply by 99. The product is:
- first two digits are 43: 43
- next repeating digits are repeating 4's, two fewer than the repeating 4's in the original number: 99
- last two digits are 56: 56.
3. So 4444 × 99 = 439956.

See the pattern?

1. If the first number is 444444:
2. Multiply by 99. The product is:
- first two digits are 43: 43
- next repeating digits are 4's, two fewer than the repeating 4's in the original number: 9999
- last two digits is 56: 56.
3. So 444444 × 99 = 43999956.