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7 96 REDUCTION OF AVOIRDUPOIS WEIGHT.

KEY TO CARD No. 29.

LESSON 9.

in 4? 1. 4 in 9? 2. and 1 cwt.

from

Take 12 cwt. O qrs. 25 lb. (over which make 4 quarters.

49
much remains ?
Answer, 36 cwt. 3 qrs. 22 lb.

12

=36

Read thus,

12

25

36

cwt. 49 12

qrs. 0

Ib. 19

cwt. O qrs. 19 lb. how

Then 4 in 4? 1. 4 in 19? 4 times and 3 over.

Three pounds make 48 49 cwt. O qrs. 19 lb.

ounces; 4 in 48? 12 times.
0 25

LESSON 11.
3
22

Forty-four seamen take in

a prize 82 cwt. 2 qrs. 22 lb. 49 cwt. 0 qrs. 19 lb.

of indigo: What quantity will less

be left for the ship after giv0

ing each man 105 lb. 4 oz.? equals

Answer, 41 cwt. I qr. 11 lb,
3 22

DIRECTIONS.
OPERATION.

Reduce the 105 lb.into qrs.
by 28, that is, 105--28=3 and

21 lb. over, or 105 lb. 4 oz. 0 25

equals 3 qrs. 21 lb. 4 oz.

Multiply this quantity by 36 3 22

11 and by 4, the product will
Addition and Subtraction. be the same as if multiplied
In these Rules we carry at|by 44, the number of men,

Ib.
every 16 in the drams and
ounces, at 28 in pounds, at 4

28)105(3 qrs.

84
in quarters, and at 10 in hun-
dreds; but if we wish to

21
make tons, then carry at 20
in the hundreds.

.

OZ.

3 21 LESSON 10.

11 If 49 cwt. 19 lb. of tobacco be transported on 4 wag- 10 1 9 12 gons, what weight will each

4 carry on an average ? Answer, 12 cwt. 1 qr. 4 lb.

41

1 11 0 12 oz.

Thus 44 men will receive oz. ||11 cwt. I qr. 11 lb.; which

o quantity must be subtracted 1 4 12 from the whole, viz. 82 cwt In this operation we say 4 || 2 qrs. 22 lb.

cwt.

qrs. lb.

4

cwt. 4)49

12

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Ib.

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19

| KEY TO CARD No. 29.

OPERATION.

In multiplying 3 qrs. 21 lb. A. cwt. qrs. lb.

4 oz. we say, 82 2 22

11 times 4 are 44 oz. 44 41 1 11

ounces make 2 lb. 12 oz.; set

12 for ounces and carry 2 to 41 1 11 for the ship. || the pounds.

Pounds. Eleven times 21 are 231 and 2 we carried make 233lb. 28 in 233? 8 times and 9 over; this makes 8 quarters and 9 pounds; set down 9 and carry 8 to the quarters.

Quarters. Eleven times 3 are 33 and 8 we carried are 41. 41 quarters make 10 cwt. 1 qr.

Then we multiply 10 cwt. 1 qr. 9 lb. 12 oz. by 4: the product is 41 cwt. 1 qr. 11 lb. to be given to the 44 seamen.

OPERATION IN WORDS.

Ounces. Four times 12 are 48: 48 ounces make 3 lb.; carry 3 to the pounds.

Pounds. Four times 9 are 36 and 3 we carried make 39 lb. or I qr. 11 lb. ; set down 11 and carry 1 to the quarters.

Quarters. Four times 1 is 4 and 1 we carried makes 5: 5 quarters make 1 cwt 1 qr.; set down I and carry 1 to the hundreds.

Hundreds. Four times 10 are 40 and I we carried makes 41. Subtract this quantity from 82 cwt. 2 qrs and 22 lb., the remainder will belong to the ship. See operation marked A.

REMARKS. The perplexity of boys in working the four last lessons, is a sufficient evidence of mismanagement during past ages.

It has been too fashionable to puzzle young beginners in arithmetic, with all the weights and measures when they are learning Addition and Subtraction.

KEY TO CARD No. 29.

Their minds are thereby overcharged with various, intricate, and unpleasing objects, before they are informed with a practical knowledge in figures.

The consequences of which have been, a loss of time, discouragement, and a forsaking of arithmetic.

It is hoped that these hints will serve to relieve ciphering classes in future, from so needless a burden.

LESSON 12. Bought 157 barrels of sugar, weighing in gross, 363 lb. each: Tare, 27 Ib. a barrel.

How many pounds neat? N. B. Merchandise weighed in boxes, bags, barrels, &c. is called gross; but after the tare, that is, the weight of the boxes, bags, &c. is subtracted, the weight is called neat.

DIRECTIONS. 1. Multiply the number of barrels by the tare per barrel, the product will be 4239 for tare.

2. Multiply the number of barrels by the gross weight of each barrel, the product will be 56991 for the gross; subtract the tare from the gross, the remainder will be neat

OPERATION.
157 barrels.
27 lb. tare per barrel. 157 barrels.

363 lb. gross.

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TROY WEIGHT.
24 grains, marked gr. make 1 pennyweight,
20 pennyweights,

1 ounce,
12 ounces,

1 pound,

pwt.

OZ.
Ib.

KEY TO CARD No. 29.

By this weight, gold, silver, jewels, electuaries, and all liquors are weighed; but it is seldom used in the United States.

Merchants that receive considerable sums of gold, overseers of the mint, banking houses, and silversmiths, make use of this weight.

Note.-A carat is the twenty-fourth part of any quantity or weight. Twenty-two carats of gold, and 2 carats of copper melted together, make the standard for gold. Eleven oz. 2 pwts. of fine silver, melted with 18 pwts. of

copper,

make the true standard for silver coin. In these cases copper is called alloy.

LESSON 1. In 30 lb. 11 oz. how many pennyweights ? 12 ounces in a pound.

Ans. 7420 pwts.

371

20 pennyweights in an ounce.

7420

LESSON 2. In 8 lb. 3 oz. 15 pwts. of silver, how many spoons of 4 oz 15 pwts. each?

Ans. 21 spoons.

. DIRECTIONS. Reduce the whole quantity, 8 lb. 3 oz. 15 pwt. into pennyweights for a dividend.

Reduce the weight of each spoon into pennyweights for a divisor; the quotient will be the answer.

OPERATION.
Ib. oz. pwt.

OZ. pwt.
8 3
15

4 15 12

20

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KEY TO CARD No. 29.

LESSON 3. Troy Weight. A gentleman having 10 lb. 3 oz. of silver, wished to make candlesticks of i lb. cups of 6 oz. table spoons of 2 oz. and tea spoons of į an ounce, and to have an equal number of each; what was that number? Ans. 6 of each.

DIRECTIONS. 1. Reduce the given quantity of silver, viz. 10 lb. 3 oz. to pennyweights for a dividend.

2. Reduce each article to pennyweights and add them: Take the amount for a divisor.

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lb. oz.

pwt in a

lb. 10 3

1x12x20=240 candlestick. 12 oz. in a pound. 6 oz. X 20=120 cup.

2 oz. x 20= 40 table spoon. 123 oz.

} oz.

= 10 tea spoon. 20 pwt. in an ounce.

410 Amount. 2460 pwt. the quantity of silver.

2460-410=6 for answer.

APOTHECARIES' WEIGHT.
The denominations are :

20 grains, marked gr. make 1 scruple, э
3 scruples,

· 1 dram, 3
8 drams,

1 ounce, 3 12 ounces,

1 pound, Ib. Apothecaries mix their medicines by this weight; but buy and sell by Avoirdupois.

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