## BEATCALC:  Beat the Calculator!

Back to Calculation Tips & Tricks

 From B. Lee Clay

Squaring Numbers

Multiplying Numbers

Dividing Numbers

Subtracting Numbers

Finding Percents

Calculation
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### Multiplying a repeating 6's number by 88

1. Choose a repeating 6's number (666, etc.)
2. Multiply it by 88
3. The product is:
- the first two digits are 58.
- the next digits are repeating 6's (two fewer than repeating 6's in the original number).
- the last two digits are 08.

#### Example:

1. If the first number is 66666:
2. Multiply by 88. The product is
- the first two digits are 58: 58.
- the next digits are repeating 6's (two fewer than repeating 6's in the original number): 666.
- the last two digits are 08.
3. So 66666 × 88 = 5866608.

See the pattern?

1. If the first number is 666666666:
2. Multiply by 88. The product is
- the first two digits are 58: 58.
- the next digits are repeating 6's (two fewer than repeating 6's in the original number): 6666666.
- the last two digits are 08: 08.
3. So 666666666 × 88 = 58666666608.
With these three steps you will be able to give these products, some of which your friend's calculator will not be able to accommodate.