## BEATCALC:  Beat the Calculator!

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 From B. Lee Clay

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### Multiplying a repeating 4's number by 66

• Choose a repeating 4's number (444, etc.)
• Multiply it by 66
• The product is:
- first two digits are 29
- next digits are repeating 3's - two fewer than the repeating 4's in the original number
- last two digits are 04.

#### Example:

1. If the first number is 444:
2. Multiply by 66. The product is:
first two digits are 29: 29.
next repeating digits are repeating 3's, two fewer than the repeating 4's in the original number: 3.
last two digits are 04: 04.
3. So 44 × 66 = 29304.

See the pattern?

1. If the first number is 44444:
2. Multiply by 66. The product is:
first two digits are 29: 29.
next repeating digits are 3's, two fewer than the repeating 4's in the original number: 333.
last two digits are 04: 04.
3. So 44444 × 66 = 2933304.