## BEATCALC:  Beat the Calculator!

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 From B. Lee Clay

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### Multiplying a repeating 1's number by 333

1. Choose a repeating 1's number (111, etc.)
2. Multiply it by 333
3. The product is:
- first two digits are 36
- next repeating digits are 9's - two fewer than repeating 1's in the original number
- last two digit are 63.

#### Example:

1. If the first number is 11111:
2. Multiply by 333. The product is:
first two digit are 36: 36
next repeating digits are 9's, two fewer than 1's: 999
last two digits are 63: 63
3. So 11111 × 333 = 3699963.

See the pattern?

1. If the first number is 111111111:
2. Multiply by 333. The product is:
first two digit are 36: 36
next repeating digits are 9's, two fewer than 1's: 9999999
last two digits are 63: 63
3. So 111111111 × 333 = 63999999936.
Using this pattern you will be able to give these products quickly and easily.