## BEATCALC:  Beat the Calculator!

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 From B. Lee Clay

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### Multiplying a 2-digit number by 34

1. Select a 2-digit number.
2. Multiply it by 11 (add the digits from right to left).
3. Multiply by 3.
4. Add the original number.

#### Example:

1. The 2-digit number chosen to multiply by 34 is 21.
2. Multiply by 11: 11 × 21 =
- the last digit is 1
- the next digit is 1+2 = 3
- the first digit is 2: 231
3. Multiply by 3: 3 × 231 = 693
4. Add the original number: 693 + 21 = 714
5. So 34 × 21 = 714.

See the pattern?

1. The 2-digit number chosen to multiply by 34 is 52.
2. Multiply by 11: 11 × 52 =
- the last digit is 2
- the next digit is 2+5 = 7
- the first digit is 5: 572
3. Multiply by 3: 3 × 572 = 1500 + 210 + 6 =
1710 + 6 = 1716
4. Add the original number: 1716 + 52 = 1768
5. So 34 × 52 = 1768.

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