## BEATCALC:  Beat the Calculator!

Back to Calculation Tips & Tricks

 From B. Lee Clay

Squaring Numbers

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Dividing Numbers

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### Multiply an integer + 1/2 times the number + 1

1. Choose a one-digit number (1-9).
3. Multiply the sum by a second number (mixed fraction) that is one greater.
4. Add 1 to integer (base) of second number.
5. Multiply by integer (base) of first number.This is integer (base) of answer.
6. Add 3/4. This is product of multiplication.

#### Example:

1. If the number selected is 2:
2. Multiply 2 1/2 by 3 1/2.
3. Add 1 to second integer. 3 + 1 = 4
4. Multiply this by first integer. 4 × 2 = 8 (Base of answer)
5. Add 3/4. Product is 8 3/4.
6. So 2 1/2 × 3 1/2 = 8 3/4.

See the pattern?

1. If the number selected is 8:
2. Multiply 8 1/2 × 9 1/2.
3. Add 1 to second integer. 9 + 1 = 10
4. Multiply this by first integer. 10 × 8 = 80 (Base of answer)
5. Add 3/4. Product is 80 3/4.
6. So 8 1/2 × 9 1/2 is 80 3/4.