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MULTIPLICATION.

49. 1. Henry worked 5 days per week for 5 weeks. How many days did he work in that time?

2. A boy delivered books to 12 houses, leaving 6 books at each house. How many books did he carry altogether? 3. The wages of a laborer were $12 per week. How much could he earn in 6 weeks?

4. The price of a cord of wood is $5. How much must be paid for 7 cords?

5. The postman who delivers our mail travels 9 miles per day. How far will he travel in 8 days?

6. A lady bought 11 yards of cambric at 10 cents per yard. How much did it cost her?

7. A good walker can walk 4 miles per hour. How far can he walk in 9 hours at that rate?

Nine 5's?

Eight 6's?
Nine 4's?

8. How many are eight 3's? 9. How many are seven 7's? 10. How many are six 8's? 11. How many are four 6's? 12. What have you been doing with the numbers in the examples given above?

Five 4's?

50. A short process of finding the sum of several equal numbers, or the process of taking one number as many times as there are units in another is called Multiplication.

51. The number taken or multiplied is called the Multiplicand.

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52. The number which shows how many times the multiplicand is taken is called the Multiplier.

53. The result obtained by multiplying is called the Product.

54. The multiplicand and multiplier are called the Factors of the product.

55. The Sign of Multiplication is an oblique cross, X. It is read multiplied by when the multiplicand precedes it and times when the multiplier precedes it.

Thus 6 x 8 is read 6 multiplied by 8 when 6 is the multiplicand, but it is read 6 times 8 when is the multiplier.

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11 22 33

44 55 66

77 88

99 110 121 132

12

24 36 48 60 72 84 96 108 120 132 144

EXPLANATION. -The numbers in the left-hand column may be regarded as the multipliers, and the numbers across the top as the multiplicands. The products will be found in the horizontal columns opposite the multipliers.

Thus, 2 ones are 2; 2 twos are 4; 2 threes are 6; 2 fours are 8, etc. The order may be changed so that the numbers in the upper horizontal line may be regarded as the multipliers, and the numbers on the left as the multiplicands. Each successive multiplier may be used with each multiplicand.

Thus, 1 two is 2; 2 twos are 4; 3 twos are 6; 4 twos are 8, etc.

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56. When the multiplier is not greater than 12.

ORAL EXERCISES.

1. When oranges cost 4 cents apiece, how much must Mary pay for 6 oranges?

2. If Lulu changes 6 half-dimes into cents, how many cents will she have?

3. Henry went to school every school-day for 8 weeks. How many days was that?

4. A girl bought 9 yards of ribbon for 8 cents a yard? How much did it cost her?

5. An organ-grinder received 7 cents at each of 8 houses. How much did he get in all ?

6. A boy sold 9 pencils at 4 cents apiece. How much did he get for them all?

7. In a school-room there were 8 rows of seats, and 8 seats in a row. How many pupils could be seated there? 8. A half-quire of paper contains 12 sheets. How many sheets are there in 6 half-quires?

9. A drawing book cost 12 cents. If each pupil in a class of 9 pupils paid the same price for a drawing book, how much did they all pay?

10. Harry had to pay 9 cents per day for his fare in going to and from school. How much was that per week?

11. Alice planted 9 rows of asters in her flower bed, and each row had 9 plants. How many asters did she set out? 12. Each pupil in a class wrote 7 lines in his writing book. If there were 7 pupils in the class, how many lines did they all write?

13. The cost of a railroad ticket from Ashburn to Gray stone is 11 cents. How much will 8 such tickets cost?

14. Some children are required to attend school 6 hours per day. How many hours will they be at school in 7 days?

15. If Mary goes to bed at 8 o'clock at night, and rises at 7 o'clock in the morning, how many hours does she spend in bed in 9 days?

16. Reuben said that he saw 5 flocks of birds, each containing 7 birds. How many birds did he see?

17. A school week is 5 days. in 9 school weeks?

How many days are there

18. Sarah made on her slate 9 rows of squares, each row containing 7 squares. How many squares did she make ? 19. Henry brought home 5 dozen eggs. How many eggs did he bring?

20. Susie's father worked 9 hours per day for 7 days. How many hours did he work in all?

21. How many are two 2's? Three 2's? Four 2's? Five 2's? etc. Give the table of 2's.

22. Give the table of 3's. Of 4's. Of 5's. Of 6's.

7's. Of 8's. Of 9's. Of 10's.

23. Count by 5's from 0 to 100 20, 25, 30, etc.

Of 11's. Of 12's.

24. Count by 3's from 0 to 36. 25. Count by 6's from 0 to 72. 26. Count by 4's from 0 to 48. 27. Count by 10's from 0 to 110.

Of

in this way: 0, 5, 10, 15,

By 7's from 0 to 84.
By 9's from 0 to 108.
By 8's from 0 to 96.
By 12's from 0 to 144.

WRITTEN EXERCISES.

57. 1. How many are 6 times 397 ?

Multiplicand, 397
Multiplier, 6
Product, 2382

EXPLANATION. - For convenience in multiply. ing, the multiplier is written under the multiplicand and we begin at the right to multiply in the following manner:

6 times 7 units are 42 units. But 42 units are 4 tens and 2 units; therefore, the figure 2 is written in units' place in the product, and the 4 tens are reserved to add to the tens of the product.

6 times 9 tens are 54 tens, plus 4 tens reserved are 58 tens, or 5 hundreds and 8 tens; therefore the figure 8 is written in tens' place in

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