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PRACTICAL PROBLEMS

IN MULTIPLICATION OF FRACTIONS.

Required the cost of

Ans. $39.

Ans. $0.751.

Ans. $6.437. Ans. $1.20§. Ans. $5013. Ans. $24818. Ans. $565.

1. 9 yards of cloth at $4 a yard. 2. 83 quarts of nuts at 84 cts. a quart. 3. 251 yards of muslin at 25 cts. a yard. 4. 163 pounds of sugar at 74 cts. a pound. 5. 281⁄2 barrels of sugar at $173 a bar. 6. 46 cords of wood at $53 a cord. 7. 38 tons of hay at $143 a ton. 8. 53 tons of coal at $83 a ton. 9. 5 dozens of eggs at 121 cts. a dozen. 10. 963 lb. of cotton at 16 cts. a pound. 11. 85 lb. of meat at 183 cts. a pound. 12. 19 barrels of sugar at $21 a barrel. Ans. $43011. 13. What is the value of 2× 19 × 335×1378? Ans. 45.

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10000

17. Of (7)2×(†)3 × (?) 1 ?

18. Of (1)2 × (75) 3 × § 7 ?

3

2

Ans. $4681.

Ans. $0.717.

Ans. $15.95. Ans. $16.08.

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19. Of (7)3× (18) 2 × (75)1× (4)5 × (51)1? Ans. 3675

20. Of (+)× 1 3 × ( 2 1 − 3 %)?

21. Of (}{+15)× (31—33)×927 × 1 9 ? 22. Of 1017—(22%−195)+163×}}?

92416*

Ans. 665 864.

Ans. Ans. 10917.

126

23. (161+277)—(563—493)+95×71? Ans. 715,5%. 24. When St. Louis flour is worth $63 a barrel, how much will 26 barrels cost? Ans. $1703.

25. Bought 10 dozen O. H. Swedes carpet tacks, amounting to $20.40, with a deduction first of and after of &; what was the bill? Ans. $15.60%. 26. A bill of books amounts to $5963, but I get off for wholesale and for cash; what do I pay? Ans. $373388. bought some sheep for $751, and then sold apiece, and traded the rest for half a barrel

27. A farmer

7 of them at $7

of sugar at $20 a barrel, and a barrel of mackerel at $15 a

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DIVISION OF FRACTIONS.

244. Division of Fractions is the process of dividing when one or both terms are fractional.

245. There are Three Cases:

1st. A fraction by an integer; 2d. An integer by a fraction; 3d. A fraction by a fraction.

CASE I.

246. To divide a fraction by an integer.

1. Divide 13 by 6, also by 7.

SOLUTION.- divided by one equals, hence divided by 6 equals of, which is 13; } divided by 7 equals of 13, or 1.

SOLUTION 2D.-Dividing the numerator by 6, we have 6 equals (Prin. 2); multiplying the denominator by 7, we have 7 equals (Prin. 3).

2. Divide 627 by 6.

12

91

SOLUTION.-Dividing 627 by 6 we have 104 and a remainder of 3; 3 equals 12, which, added to 2, equals ; divided by 6 equals ; hence the quotient is 104ğ.

OPERATION.

13÷6=1's

OPERATION.

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OPERATION.

6)627

104ğ

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NOTE.-Reduce a mixed number to a fraction, or divide the integer, unite the remainder with the fraction and divide the result.

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247. To divide an integer by a fraction.

1. Divide 12 by the fraction §.

SOLUTION.-12 divided by one equals 12, hence

12 divided by equals 7 times 12,

and 12 divided by equals of 7 times 12, which is times 12, which equals 14. Hence the following

OPERATION.

12÷
12 × 1 = 14

=

Rule I.-Multiply the dividend by the denominator of the fraction, and divide the product by the numerator.

Rule II.-Invert the divisor and proceed as in multiplication of fractions.

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SOLUTION.- divided by one equals, hence divided by equals 6 times, and divided by equals of 6 times, which is g times, which equals.

SOLUTION 2D.- equals 1, equals, and # divided by # equals 48 divided by 45, which equals or 18.

OPERATION.

=

OPERATION.

8÷5=18÷÷35= 48451818

Rule I.-Multiply the dividend by the denominator of the divisor, and divide by the numerator.

Rule II.-Invert the divisor and proceed as in multiplication of fractions.

NOTES.-1. Reduce mixed numbers to simple fractions. When the divisor is a compound fraction, invert each term and multiply, cancelling when possible.

2. " Why do we invert the divisor?" The analysis requires it, or dictates it, as is shown in first solution. This reply is better than "for convenience."

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PRACTICAL PROBLEMS

IN DIVISION OF FRACTIONS.

1. If 7 yards of cloth cost $47, what is the price per yard? Ans. $61.

2. If 18 tons of hay cost $2853, what is the price per ton? Ans. $153.

3. If 23 bags of coffee cost $410, what is the price per bag? Ans. $17.

4. If 17 barrels of sugar cost $23818, what is the price per barrel? Ans. $137. 5. If 371⁄2 tons of coal cost $253, what is the price per ton? Ans. $63.

6. If 9615 acres of land cost $676124, what is the price per acre? Ans. $693. 7. If 867 cords of wood cost $68025, what is the price per cord?

8. What is the value of 2×43 × 18 ÷ 3 ?

9. Of $99××4088-318?

561 792 720

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Ans. $75.

Ans..

Ans. 35.

Ans. 1.403

2187

Ans. 584

Ans. 400000 407511

12. Of (21×2}+5 of 7)× (§)3÷(77—33×48) ?

Ans. 1.

13. Find the value of 541-177× (64+31-2})÷ 276-815. 14. If of 3 gallons of kerosene cost of 93, what will

1 gallon cost?

Ans. $.

15. The product of two numbers is 156, and one of them is 131; what is the other?

Ans. 115.

16. What number is that which being multiplied by of 4 of 91, will produce 177? Ans. 217.

17. If 4 men plow 20 acres in 5 days, how much at the same rate would 6 men plow in 7 days? Ans. 4418.

18. Mr. Shaw bought 871⁄2 bushels of corn for $109g, and sold of the quantity to Mr. Landis at a profit of $2 per bushel; what did he receive for the part sold? Ans. $1163.

REDUCTION OF COMPLEX FRACTIONS.

249. The Reduction of Complex Fractions is the process of changing them to simple fractions.

NOTE.-A complex fraction is not really a fraction, according to the definition of a fraction. It is rather a complex fractional expression of

one fraction divided by another.

1. Reduce to a simple fraction.

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Rule I.-Multiply the numerator of the complex fraction by its denominator inverted.

Rule II. Multiply both terms of the complex fraction by the least common multiple of the denominators.

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