## BEATCALC:  Beat the Calculator!

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 From B. Lee Clay

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### Multiplying a repeating 4's number by 44

• Choose a repeating 4's number (444, etc.)
• Multiply it by 44
• The product is:
- first two digits are 19
- next digits are repeating 5's - two fewer than the repeating 4's in the original number
- last two digits are 36.

#### Example:

1. If the first number is 444444:
2. Multiply by 44. The product is:
first two digits are 19: 19.
next repeating digits are repeating 5's, two fewer than the repeating 4's in the original number: 5555.
last two digits are 36: 36.
3. So 444444 × 44 = 19555536.

See the pattern?

1. If the first number is 444444444:
2. Multiply by 44. The product is:
first two digits are 19: 19.
next repeating digits are 5's, two fewer than the repeating 4's in the original number: 5555555.
last two digits are 36: 36.
3. So 444444444 × 44 = 19555555536.
Big products like these will overwhelm your friend's normal calculator. Easy win for mental math answers here.

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