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SHORT METHODS

IN

MULTIPLICATION AND

DIVISION.

Art. 1. To multiply a number by 50: Multiply of the number by 100. Why?

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(b) Find the sum of the twelve products.

Art. 3. To multiply a number by 52: number, to which add twice the number.

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Take 50 times the Why?

=

1700+ 68 1768
2250+90= 2340

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27 by 52

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(c) Find the sum of the twelve products.

Art. 4. To multiply a number by 49: Take 50 times the number, from which subtract the number itself. Why?

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(d) Find the sum of the twelve products.

Art. 5. To multiply a number by 33: Multiply of the

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(e) Find the sum of the twelve products.

Art. 6. To multiply a number by 341: the number, to which add the number itself.

Take 33 times
Why?

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(f) Find the sum of the twelve products.

Art. 7. To multiply a number by 35: the number, to which add twice the number.

Take 33 times
Why?

800 +48 848

=

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24 × 351
25 × 35

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33

times 25 = 8331

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(g) Find the sum of the twelve products.

Art. 8. To multiply a number by 321: Take 33 times the number, from which subtract the number itself. Why?

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(h) Find the sum of the twelve products.

Art. 9. To multiply a number by 25: Multiply of the number by 100. Why?

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(i) Find the sum of the twelve products.

Art. 10. To multiply a number by 26: Take 25 times the number, to which add the number itself.

Why?

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(j) Find the sum of the twelve products.

Art. 11. To multiply a number by 27:

number, to which add twice the number.

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Take 25 times the Why?

900+72=972

36 × 27

25 times 36 = 900

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(k) Find the sum of the twelve products.

Art. 12. To multiply a number by 24: Take 25 times the number, from which subtract the number itself. Why?

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(1) Find the sum of the twelve products.

Art. 13. To multiply a number by 20:

Multiply of the number by 100. How may a number be multiplied by 21?

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(m) Find the sum of the twelve products.

Art. 14. To multiply a number by 163: Multiply of the number by 100. How may a number be multiplied by 17? by 18? by 15?

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(n) Find the sum of the twelve products.

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