EXAMPLES FOR PRACTICE.

3. If 1 acre of ground cost 23 dollars, what cost 62,123 acres? Ans. 1,428,829 dollars. 4. If 1 pipe of wine contain 1,008 pints, what will 19 pipes contain ? Ans. 19,152.

5. If, in digging a canal, 35,432 cubic yards are excavated in 1 day, how much will be excavated in 29 days? Ans. 1,027,528 yds. 6. If 33 dollars be paid a soldier, how much must be paid an army of 65,217 men? Ans. 2,152,161.

7. Multiply 151X29 Ans. 4,379 | 13. 28,933×41

8. 623X19

9. 7,512×17

11,837 14. 36,856×37 127,704 15. 72,945×47

§ XV. 1. At 10 cents a pound, what cost 53 pounds

of butter?

Here the product is the same as the multiplicand, with a cypher annexed.

2. At 10 cents apiece, what will 25 oranges cost? Here 10 is the multiplier, again.

Here, again, the product is the same as the multiplicand, with a cypher annexed.

It seems, then, that annexing a cypher at the right of any number, multiplies it by 10.

The reason of this is very plain, when we consider that a figure in the tens' place, is ten times as great as the same figure in the units' place; because numbers increase towards the left, in ten-fold proportion. Also,

A figure in the hundreds' place, is ten times as great as the same figure in the tens' place. And, universally,

A figure in any place, is ten times as great as the same figure, in the next right hand place.

If a figure be removed, then, from the units' to the tens' place, from the tens' to the hundreds', or from any place to the next higher, it will become ten times as great as before; that is, it will be multiplied by 10.

Annexing a cypher to a number, removes every figure of that number a place higher. It therefore makes every figure ten times greater, and multiplies the whole number by 10.

Annexing two cyphers, removes every figure two places higher, and consequently multiplies the whole number by 100.

Annexing three cyphers, multiplies by 1,000, four cyphers, by 10,000, and so on.

When we use the word ANNEX, we mean PLACE AT THE RIGHT; when we use the word PREFIX, we mean

PLACE AT THE LEFT.

It will be seen that the number of cyphers, annexed, is just equal to the number of cyphers in the multiplier. Hence,

WHEN THE MULTIPLIER IS 1, WITH CYPHERS Annexed, multiPLICATION IS PERFORMED BY ANNEXING THE SAME NUMBER OF CYPHERS TO THE MULTIPLICAND.

EXAMPLES FOR PRACTICE.

2. At 10 dollars a barrel, what cost 357 bbls. of flour? Ans. 3,570 dolls.

3. If I were to give 75 men 100 dollars apiece, what should I give the whole? Ans. 7,500 dolls.

4. What would 275 pounds of beef come to, at 10 cts. pr. pound. Ans. 27 dolls. 50 cts.

The money of the UNITED STATES, is called FEDERAL MONEY. It is reckoned in EAGLES, DOLLARS, DIMES, CENTS and MILLS. These are called its denominations.

FEDERAL MONEY.

10 mills (marked m.) make 1 cent, marked ct.
66 1 dime 66 di.

10 cents

10 dimes

10 dollars

of that value.

NOTE. The mill is merely a nominal coin, since there is no real coin in use.

MENTAL EXERCISES.

1. How many cents in 2di? in 3di? in 5di? in 7di? in 12di?

2. How many dimes in 2 dolls? in 3 dolls? in 4 dolls? in 7 dolls? in 9 dolls?

3. How many mills in 2 cts? in 3 cts? in 4 cts? in 5 cts? in 9 cts? in 10 cts?

4. How many mills in 1 di.? in 2 di.? in 3 di.? in 4 di.? in 5 d.? in 7 d.? in 10 d.?

5. How many mills in 1 doll? in 2 dolls? in 3 dolls? in 4 dolls? in 10 dolls?

6. How many mills in 1 E.? in 2 E.? in 3 E.? in 7 E.? in 9 E.? in 10 E.?

Then, it seems that a dollar is 10 dimes, or 100 cents, or 1,000 mills. Hence,

DOLLARS ARE MADE DIMES BY ANNEXING ONE CYPHER; CENTS BY ANNEXING TWO CYPHERS; AND MILLS BY ANNEXING 3 CYPHERS.

If a sum be cents all the even hundreds will be dolls., of course; if it be dimes all the even tens will be dolls.; if it be mills, all the even thousands will be dolls. Hence,

TO CHANGE A SUM FROM DIMES TO DOLLARS, POINT OFF ONE FIGURE ON THE RIGHT; FROM CENTS TO DOLLARS POINT OFF TWO FIGURES; FROM MILLS TO DOLLARS, POINT OFF THREE FIGURES. ALL ON THE LEFT OF

THE POINT WILL BE DOLLARS.

For this purpose a period (:) is the most convenient point. It is called the SEPARATRIX, because it is used to separate dollars from lower denominations. With the exception of this point the numbers follow one after another like common numbers. If there be but one figure after the point, the number may be read, dollars and dimes, or the whole may be read as dimes. If two figures follow the point, the number may be read dollars dimes and cents, or dollars and cents, or all together as cents. If three, dollars, dimes, cents and mills, or, cents and mills, or all together as mills. Many more variations in reading these numbers may be made, but it is of no use to repeat them, since they are not used in practiee. The teacher, if he sees fit, may require them of the pupil, who will readily discover them for himself.

dolls.

Accounts are kept in dollars and cents, the other denom inations being disregarded. Thus instead of writing 3 E. 5 dolls. 4 di. 6 cts, we write 35 dolls. 46 cts. or, which more common $35.46. When the character $ is placed

before a number, the names of the other denominations are omitted, and dollars are to be understood for the figures before the separatrix, cents for the first two after it, and mills for the third, if there be any. Hence, to read Federal Money,

CALL ALL THE FIGURES BEFORE THE SEPARATRIX, DOLLARS, AND ALL AFTER IT CENTS, OR CENTS AND MILLS.

To write Federal Money. WRITE EAGLES AND DOLLARS, TOGETHER

AS DOLLARS; AND PLACE THE SEPARATRIX: THEN WRITE DIMES AND CENTS TOGETHER AS CENTS, AND MILLS, IF THERE BE ANY, next.

In adding or subtracting Federal Money, the pupil must be careful to add or subtract the same denominations to or from each other; that is dollars, to or from dollars; cents, to or from cents, &c.

EXAMPLES FOR PRACTICE, CONTINUED.

5. How many cents are there in 700 dollars? Ans. 70,000. 6. How many mills are there in $965.13? Ans. 965,130.

7 What would 642 gallons of brandy cost at $1.00 pr. gal? 8. What would 987 barrels of flour cost at $10.00 pr. barrel ? Give the several answers in dolls. cents and mills.

9. What cost 954 pounds of cheese at $0.10 pr. pound?

§ XVI. 1. At 20 cents a pound, what will 78 pounds of sugar cost.

Here 20 is the multiplier.

But 20 is a composite number, because it is 2 tens or 2 times 1 ten.

Its factors, then, are 2 and 10.

By the rule for composite numbers, multiply first by 2,

thus, 78

2. On one page of a book are 47 lines, how many on 60 ? Here 60=6×10 is the multiplier. Ans. 2,820

3. At 48 dollars a hogshead, what cost 500 hogsheads of molasses? Here 500 5X100 is the multiplier. Ans. 24,000

In all these examples, we multiply by the significant figures of the multiplier, and annex the cyphers to the product.

It is plain that if there are cyphers at the right of the multiplicand, these will, likewise, be found at the right of the product. For example, multiply 30 by 3;

thus,

Multiply 500 by 9

30

.3

90 Ans.

500

4500 Ans.

Here we have the same cyphers at the right of the products, which were at the right of the multiplicands. Hence,

WHEN THERE ARE CYPHERS AT THE RIGHT OF EITHER OR BOTH FACTORS, MULTIPLY BY THE OTHER FIGURES, AND ANNEX ALL THE CYPHERS TO THE PRODUCT.

NOTE. If the significant figures of the multiplier form a composite number, we may multiply by them according to the rule of composite numbers, and then annex cyphers. In the same manner we may take advantge of any of the preceding rules.

EXAMPLES FOR PRACTICE.

4. If 60 men can do a piece of work in 79 days, how many days will it take 4 men to do it? Ans. 4,740 days.

5. If 27 men can do a piece of work in 300 days, how many men Ans. 8,100 men.

will it take to do it in one day?

ny cents is that for the whole ?

6. If 500 labourers on a canal be paid 75 dollars a piece, how ma. Ans. 3,750,000 cents. 7. If there are 275 pages in a book, how many pages are there in an edition of 7,000 books? Ans. 1,925,000. 8. If 742 pounds of provision will serve a garrison 1 day, how many will serve 300 days? Ans. 222,600. 9. If $250.00 will gain $15.00 interest in one year, what will it gain in 70 years? Give the answer in mills. Ans. 1.050,000 mills. 10. Ifa sum of money will gain $25.00 interest in one year, how much will it gain in 50 years? Give the answer in dimes.

Ans. 12,500 dimes. 11. If $900.00 gain a certain interest in a year, what sum will gain 320 times as much? Give the answer in cents.

Ans. 28,800,000 cts.

12. If 600 barrels of rum cost 50 dollars each, what cost the whole? Give the answer in mills.

Ans. 30,000,000 mills.