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KEY TO CARD No. 27.

4. Division.

The number of decimal places in the divisor and quotient counted together, must be equal to those in the dividend. NOTE 1. If decimal places be wanting in the dividend, annex so many ciphers as you please.

2. If there be decimal places wanting in the quotient, supply the defect by prefixing ciphers.

These Rules shall be more fully explained, when we work by them separately.

CASE 2.

To find the integral value of a decimal.

RULE.

Multiply the fraction by the denominations of the integer, and point off the decimal parts to the right; the left will be integers; as in Lesson 7.

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By what rule do we point off decimals in multiplication? By counting the decimal places in both factors; that is in the multiplicand and multiplier: Then begin at the right of the product and count so many towards the left as were in the two factors; there place the point. The figures on the left are integers. See Rule 3.

NOTE. If there be not so many figures in the product as are in the two factors, supply the defect by prefixing ciphers to the left hand.

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EXAMPLE.

Here are three decimals in the upper factor, and there is one in the lower;

therefore we must have four in the product.

REMARKS.

It is of importance to know the place of the decimal point; because decimals decrease in a tenfold proportion towards the right, as whole numbers increase towards the left.

KEY TO CARD No. 27.

In the above example, if the cipher had not been prefixed, the number would read .032 66 thirty-two thousandths." Whereas the true number is "thirty-two ten thousandths.”

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Answer, 87.5 cents.

In this result or product it

Pence, 9.00

Answer, 9 pence.

LESSON 16.

How many shillings in .95

of a pound?

.95×20

20

Shillings, 19.00

Answer, 19 shillings.

LESSON 17.

What is the value of .8125

of a shilling?

.8125
12

Pence, 9.7500

4

may be observed that the Farthings 3.0000

fraction is five hundred thousandths; but that is the same as fifty hundredths, or five tenths.

LESSON 14.

In .8 of a dollar, how many cents?

Answer, 9d. 3q.

LESSON 18.

What is the proper quantity of .0625 of a hundred weight, or 112 pounds?

.0625

112.

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KEY TO CARD No. 27.

LESSON 19.

LESSON 22.

What number of pounds

What is the proper value

Avoirdupois are in .1875 of of.1875 of a pound currency?

a hundred weight?

.1875

112.

3750

20625

£.1875

20s.

Shillings, 3.7500

12

Pence, 9.0000

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Answer, 3s. 9d.

CASE 3.

LESSON 23.

Reduce 15s. 9d. 3q. to the decimal of a pound.

How shall we reduce quantities of several denominations, such as, shillings, pence & farthings; quarters, pounds, ounces, &c. to a decimal?

RULE.

1. Begin a column with the least denomination and proceed downwards to the greatest, thus,

20s.

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Shillings, 15.812500

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2. Let ciphers be ideally annexed as they really are in 3q.Lessons 3, 4, and 5.

3. Begin at the top and diRead the above question vide each number by its vathus: "Seven hundred and lue in the next denomination; ninety thousand six hundred that is, farthings by 4, pence, and twenty-five Millionths. by 12, shillings by 20, &c.

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KEY TO CARD No. 28.

LESSON 29.

we reduce the 6d. to the de

Reduce 2s. 6d. to the deci-cimal of a shilling, viz. .5 and mal of a dollar of 6 shillings. annex this decimal to 7s. thus,

12/6.

62.5

.41666+4
Answer, .41666+4

PROOF BY CASE 2.

.41666+4 6

Shillings, 2.50000

12

Pence, 6.00000

See Note under Lesson 9.

LESSON 30.

Reduce 3s. 9d. to the decimal of a dollar of 7s. 6d. Jersey currency. 129.

7.5 3.75(.5 Answer. 375

REMARKS.

1. As 7s. 6d. make a dollar, we must divide by it for our last divisor. And as it cannot be used in its present form,

7.5

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END OF PART SEVENTH.

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