Imatges de pàgina
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13 months, 1 day, and near 6 hours 1 folar

In a Year there are,

13 months, 1 day, 6 hours.

52 weeks, 1 day, 6 hours.

I folar year.

8,766 hours.

525,960 minutes.

365 days, 6 hours.

31,557,600 feconds.

Note. The folar year is divided into 12 unequal months, called calendar months, according to the ancient verse, which may ferve to imprefs the number of days each month con tains, on the memory:

Thirty days hath September,

April, June, and November;
February hath twenty-eight alone,

And all the reft have thirty-one.

SECT. III.

OF SUBTRACTION.

SUBTRACTION, vulgarly called Subtraction, teacheth baw to take a lefs number from a greater; and theweth the te mainder, excefs, or difference. Thus, if I take 7 from 9, there will remain 2.

Rule. Place the lefs number under the greater; obferving, that the figures of each denomination in the lefs number stand

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directly under the figures of the fame denomination in the greater number; that is, the units under units, teas under tens, and pounds, hillings, pence, ounces, drams, &c, &c. directly under the fame, as in addition. Then, beginning at the right hand, or the leaft denomination, take the value of each figure in the lefs number from that in the greater number, which stands directly over it; fetting down the remainder underneath. Proceed in this manner till the work be finiflied. But if, as it frequently happens, any fingle figure in the lefs number be greater than that in the greater number, from which it is to be taken; an unit is to be borrowed from the next figure towards the left hand of the greater number, and added to the uppermoft figure, that the bottom figure may be taken therefrom; which borrowed unit must be paid, or added to the next figure of the lefs number on the left hand.

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To fhew the use of this rule, I fay-Suppofe a merchant owed 69541, whereof he has paid $4434. to know what remains to be paid, the fums are to be fet orderly one under the other, according to the foregoing rule,, and as feen in the examples: then, beginning with the unit figures, in the firft example, I fay, take 3 from 4 and there remains 1, which I fet under the line; next take 4 from 5 and there remains 1, which is also fet under the line; again, take 4 from 9 and there remains 5, which must be fet down as before; and, laftly, take 5 from 6 and there remains 1: thus there remains due 15117.

Subtraction is proved by adding the remainder to the lefs of the two given numbers, and if the total of thefe two num bers amount to the exact fum of the greater number, the

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work is right; otherwife not: thus, in this example, I add the remainder 1511. to the lefs number 54431. and the amount is 69547.; the fame as the greater number.

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In the second example, I begin with the units, as before : faying, take 7 from 6 I cannot, but by borrowing 1 from the next figure 8, and which added to the 6 makes 16 (the 8 being the next fuperior number), I fay, 7 from 16 and there remains 9; then, for the 1 that I borrowed, I carry 1 in return to the next figure of the lefs number, faying, I that I borrowed and ois but 1, therefore, 1 from 8 and there remains 7; again, 9 from 8 I cannot, but borrowing before from the next figure, I fay, 9 from 18 and there remains 9; then for 1 that I borrowed, I must add 1 to the next figure 8, faying, 9 from 9 and there remains o (which may always be done when the two figures are the fame); again, 9 from 2 I cannot, but 9 from 12 (borrowing 7) and there remains 3; then 1 that I borrowed, added to the o, and taken from the 7, there remains 6: thus the work is finished. The proof demonftrates it right.

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Proceeding in the same manner in the third example, I say, 2 from o I cannot, but 2 from 10 (borrowing one from the 7), there remains 8; then 1 that I borrowed and 9 is 10, 10 from 7 I cannot, but 10 from 17 and there remains 7; again, I that I borrowed and 4 is 5, 5 from 3 I cannot, but 5 from 13 (borrowing 1) and there remains 8; then, 4 from o (or nothing) I cannot, but 4 from 10 and there remains 6; again, 1, that I borrowed, from 9 and there remains 8; and 4 from 12 and there remains 8; and 1 that I borrowed and 8 is 9, from 10, and there remains 1; and 1 that I borrowed and 2 is 3 from 7 and there remains 4; laftly, 1 from 3 and there remains 2.

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The number of years fince any event happened, may difcovered by fubtracting the date of the year the event happened from that of the prefent year. Thus :

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Subtraction of divers denominations is performed upon the fame principle as fubtraction of numbers of one denomination. Obferving, that when an unit is borrowed of the next higher denomination, it must be confidered according to its true intrinfic value, and must be repaid to the lower figure of the fame denomination; as will be feen in the following examples :

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In the first of these examples, beginning with the farthings, I fay, 3 farthings from 2 I cannot, but borrowing an unit from the next denomination, or 1 penuy from the 9 pence (and which added to the 2 farthings makes 6 farthings), I say, 3 farthings from 6 farthings and there remains 3 farthings, which I fet under the farthings; then for the unit I borrowed of the pence, I add 1 to the 6, faying 6 and 1 is 7; now 7 from 9 and there remains 2; then 10 from 14 and there remains 4; laftly, 10 from 17 and there remains 7; thus the remains is 71. 45. 24d. which is proved in the example.

In the fecond example, I say, 1 farthing from 3 and there remains 2 farthings, or an halfpenny; which I fet down in its proper place, viz. under the denomination of farthings; then 9 from 7 I cannot, wherefore borrowing 1 billing from the 14, and adding it to the 7 pence, which makes 19 pence, I say, 9 from 19 and there remains 10; then I that I bor

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rowed and 19 is 20, 20 from 14 I cannot, wherefore I borrow 1 pound from the pounds, which, added to the 14, makes 34 fhillings; therefore, I fay, 20 from 34 and there remains 14; then that I borrowed and 1 is 2, 2 from 3 and there remains; and 1 from 2 and there remains 1; thus, the anfwer to this fum is 11. 145. 1cd; and its proof, under the anfwer, fhews that it is right.

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If the money paid be paid at feveral times, the fums so paid are to be added together, and the total fubtracted from

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