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MULTIPLICATION TABLE.

2 times 0 are 05 times 0 are 08 times 0 are

011 times 0 are 0

2 × 1 = 25 X 1 = 58 X 1 = 811 X1=11

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3 65

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8 165

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9. 185

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22. If the interest of one dollar be 6 cents a year, what will be the interest of 2 dollars, for the same time? of 3 of 4 of 5 of 6? of 7? of 8? of 9? of 10? of 11? of 12?

23. If the interest of a what will it be for 2 years? 10? 11? 12?

dollar be 6 cents for 1 year, for 3? 4? 5? 6? 7? 8? 9?

24. At 6 dollars a week, what cost 3 weeks board? 5 weeks? 7 weeks? 9? 11? 13?

25. Two men start from Hartford towards New-Haven at the same moment. One goes 7 miles an hour, the other, 3 miles an hour. How far apart are they at the end of one hour? 2 hours? 3 hours? 6? 9? 8? 7? 11? 12? 26. Two men leave Hartford at the same moment. One goes north, and the other south. One travels 4 miles an hour, and the other 2 miles an hour. How far apart are they at an hour's end? How far in 2 hours? 3? 4? 5? 6? 7? 8? 9? 12? 11?

27. If 3 men can dig a ditch in 1 day, how many days would one man be doing it?

28. If 3 men can mow a field in 2 days, how many days would 1 man be doing it?

29. If 7 men can build a wall in one day, how many days would it take one man to do it?

30. If 4 men can make a fence in 3 days, how long would 1 man be making it?

31. If 5 men can do a piece of work in 7 days, in how many days could 1 man do it?

32. If a barrel of cider will last 10 men 4 weeks, how many weeks will it last 1 man?

33. If 8 men can do a piece of work in 5 days, how many men can do it in 1 day?

34. If 7 men can do a piece of work in 3 days, how 'many men can do it in 1 day?

35. If 9 men can live on a quantity of provision 6 weeks, how many men could live on the same provision 1 week?

36. A man purchased 8 sheep at 4 dollars apiece; 5 barrels of cider, at 2 dollars a barrel; 4 yards of cloth, at 1 dollar a yard; and 3 bushels of apples, at 3 dollars a bushel. How much did they all come to?

37. A lady bought 3 yards of ribbon for 6 cents a yard; 1 yard of silk for 50 cents; 6 needles at 1 cent apiece; 1 paper of pins at 12 cents; and 1 pair of scissors at 30 How much did they all come to?

cents.

§ XI. Let the pupil write the following exercises on his slate. 1. A man bought 5 pounds of beef at 6 cents a pound. How much did he give for the whole ?

PROCESS.

666

30

Here we set down 6, the price of a pound, 5 times, and add up the numbers. The amount is 30. But we know by the table that 5 times 6 are 30. Therefore, if we put down the 6 once, with the 5 under it, we may write down the answer immediately. Thus,

65

30

The whole process is performed, by saying 5 times 6 are 30.

Thus we see, that examples of this kind may be performed by addition, and likewise by a shorter process. Let the pupil perform, by both these methods, the following.

2. At the rate of 7 miles an hour, how far can I travel in 8 hours? 3. At 9 dollars a barrel, what will 7 barrels of flour cost? 4. At 3 dollars a ream, what will 6 reams of paper come at ? 5. At 5 cents a pound, what cost 4 pounds of pork?

Thus far, we have been repeatedly adding numbers, consisting of ane figure only. Let us now try an example in which larger numhers are concerned.

6. At 75 cents a bushel, what will 4 bushels of salt cost?

Here we have a number, consisting of 7 tens and 5 units, to be repeated 4 times.

By addition, the process would be as follows:

That is, 75 added 4 times to itself, makes 300.

75

75

75

75

30.0

75

4

20

The same may be performed as follows:

Here we say, 4 times 5 units are 20 units, and set down the 20. We then say, 4 times 7 tens are 28 tens, and set dow nthe 28, with the 8, of course, in the tens' place. We then add the two together, and the answer is 300, as before.

28

300

18

8

7. At 58 cents a yard, what will 6 yards of cloth cost? A. 348 cts. The pupil will see that he may carry, as in Addition. Thus, 8. At 18 cents a pound, what cost 8 pounds of raisins? 8 times 8 units are 64 units, equal to 6 tens and 4 units. The 4 belongs to the units' place. Reserve the 6 tens, in the mind. 8 times 1 ten are 8 tens. To the tens add the 6 144 tens reserved, and the amount is 14 tens, or 1 hundred, and 4 tens. The answer, then, is 1 hundred, 4 tens, and 4 units, or 144.

[The pupil should frequently be required to explain his processes, in the manner of the above illustrations.]

9. In one hogshead are 63 gallons. How many gallons in 7 hogsheads?

63
7

441 Ans.

10. A man has 7 lots, each containing 54 acres of ground. How many acres in all? Ans. 328. 11. A man employed 27 laborers, and gave them 4 dollars a week. How much did he give the whole a week? Ans. 108.

12. At 5 dollars a firkin, what cost 39 firkins of butter? A. 195. You see that if we were not to employ this short process in performing these examples, it would be necessary to use Addition. We have, then, found a means of per forming Addition more rapidly than by the ordinary mode. This is called MULTIPLICATION.

You see, also, that Multiplication consists in repeating the SAME number; that is, in adding the SAME NUMBER TO ITSELF. Then,

MULTIPLICATION IS A CONCISE MODE OF PERFORMING ADDITION, WHEN

THE NUMBERS TO BE ADDED ARE EQUAL.

Or,

MULTIPLICATION IS FINDING A NUMBER, EQUAL TO A GIVEN NUMBER OF REPETITIONS OF SOME OTHER NUMBER.

You see, further, that two numbers are always given you; one to be repeated, and another, which shows how often it is to be repeated.

THE NUMBER TO BE MULTIPLIED, OR REPEATED IS CALLED THE MUL

TIPLICAND.

THE NUMBER WHICH SHOWS HOW MANY REPETITIONS ARE TO BE MADE, IS CALLED THE MULTIPLIER.

THE RESULT OBTAINED FROM MULTIPLICATION, IS CALLND THN PRO.

DUCT.

Whenever two or more numbers are multiplied together, each of them is called a factor.

Then, in Multiplication, BOTH MULTIPLIER AND MULTIPLICAND ARE CALLED FACTORS.

X between two numbers signifies that they are to be multiplied together. Thus, 6X5=30, signifies that 6 multiplied by 5, equals 30.

Here is a window. A person wishes to discover how many panes of glass are contained in it. He counts the upper row of panes, and finds that there are 4 panes. He then counts the number of rows, and finds 6 rows. Then he says, 6 rows of panes, with 4 panes in each row, make up all the panes in the window. Therefore, there are 24, because 6 times 4 are 24. Another per. son counts the panes in one row up and down, and finds 6 panes. He counts the rows, and finds 4 rows. Then he says, 4 rows with 6 panes in a row, make up all the panes in the window. Therefore, there are 24 panes, because 4 times 6 are 24.

Four times 6, then, is equal to 6 times 4; because either is equal to all the panes in the window, that is, to 24.

Hence it appears that, IN PERFORMING MULTIPLICATION, EITHER

FACTOR MAY BE MADE THE MULTIPLICAND, WITHOUT ALTERING THE PRODUCT.

For convenience, however, we usually place the larger number uppermost.

EXAMPLES FOR PRACTICE.

1. What will 2 wagons cost at 23 dollars apiece ?

Ans. 46 dolls.

2. What cost 3 head of cattle at 17 dollars a head?

Ans. 51 dolls.

3. What will 18 pounds of pork cost at 4 cents a pound?

Ans. 72 cts.

4. What cost 21 barrels of cider at 3 dollars a barrel ?

Ans. 63 dolls.

5. At 5 dollars a yard, what cost 27 yards of cloth?

Ans. 135 dolls.

6. At 6 cents per pound, what cost 32 pounds of beef?

Ans. 192 cts.

7. At 7 dollars a barrel, what cost 35 barrels of flour?

Ans. 245 dolls.

8. At 8 dollars a hundred weight, what cost 43 hundred weight of sugar?

Ans. 344 dolls.

9. At 9 dollars a barrel, what cost 653 barrels of flour?

Ans. 5,877 dolls.

10. A man bought 23 kegs of brandy, each containing 9 gallons.

How many gallons did he buy?

11. He paid for it at the rate of 8 cents a quart. it come to, allowing 4 quarts to the gallon?

Ans. 207 galls.

How much did Ans. 6,624 cts.

NOTE. As 100 cents make a dollar, the pupil will readily tell how many dollars are contained in any number of cents. For all the

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