## BEATCALC:  Beat the Calculator!

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 From B. Lee Clay

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### Multiplying a repeating 4's number by 88

• Choose a repeating 4's number (444, etc.)
• Multiply it by 88
• The product is:
- first two digits are 39
- next digits are repeating 1's - three fewer than the repeating 4's in the original number
- last three digits are 072.

#### Example:

1. If the first number is 4444:
2. Multiply by 88. The product is:
- first two digits are 39: 39
- next repeating digits are repeating 1's, three fewer than the repeating 4's in the original number: 1
- last three digits are 036: 036
3. So 4444 × 88 = 391072.

See the pattern?

1. If the first number is 444444444:
2. Multiply by 88. The product is:
- first two digits are 39: 39
- next repeating digits are 1's, three fewer than the repeating 4's in the original number: 111111
- last three digits are 036: 036
3. So 444444444 × 88 = 39111111072.
Follow these three steps and you will be able to produce these big products withB ease.