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LESSON CXVI.

1. If 2 barrels of flour cost 10 dollars, what will 5 barrels cost?

2. 10 is 2 fifths of what number?

3. If 4 yards of cloth cost 40 cents, what will 9 yards cost? 4. 90 is 9 times 1 fourth of what number?

5. If 5 books cost 60 cents, what will 12 books cost? 6. 60 is 5 twelfths of what number?

7. 144 is 12 times 1 fifth of what number?

8. If 6 lead-pencils cost 36 cents, what will 11 leadpencils cost?

9. 36 is 6 elevenths of what number?

10. 66 is 11 times 1 sixth of what number?

11. If 7 quarts of cherries are worth 56 cents, what are 10 quarts worth?

12. 56 is 7 tenths of what number?

13. 80 is 10 times 1 eighth of what number?

14. If 8 boxes of strawberries are worth 160 cents, what are 12 boxes worth?

15. 160 is 8 twelfths of what number?

16. 240 is 12 times 1 eighth of what number?

17. If 9 pears are worth 27 cents, what are 5 of them worth?

18. 27 is 9 times 1 fifth of what number?

19. 15 is 5 ninths of what number?

20. If a turkey weighing 10 pounds cost 120 cents, what will a turkey weighing 7 pounds cost?

21. 120 is 10 times 1 seventh of what number?

22. 84 is 7 tenths of what number?

23. William says to Henry, who is 10 years old, your age is 1 eighth of 4 times my age; how old is William?

24. 10 is 1 eighth of 4 times what number?

25. 80 is 8 times 1 fourth of what number?

26. A lady being asked her age, answered, that her youngest daughter was 12 years old, which was 1 twelfth of 3 times her own age; what was the lady's age ?

27. 144 is 12 times 1 fourth of what number?

LESSON CXVII.

ADDITION.

ADDITION is the method of finding the total number of units contained in two or more numbers, and expressing them in one number, called the amount, or sum.

Illustration. - A man has three bags of money.

No.

1 contains 950 dollars; No. 2 contains 875 dollars; No. 3 contains 764 dollars. What is the total amount or sum of money in the three bags?

Hunds.

Tens.

Units.

950

875
764

Ans. 2,589 dolls.

We begin at the bottom of the column of units, and add all the figures in that column, and find the sum of them to be 9 units, which we write under the column of units. We then add all the figures in the column of tens, and find the sum of them to be 18 tens, or 1 hundred, and 8 tens; we write the 8 (tens) under the column of tens, and then add the 1 (hundred) with the figures in the column of hundreds, and find the sum of them to be 25 hundred, or 2 thousand, and 5 hundred; we write the 5 (hundred) under the column of hundreds, and the 2 (thousand) at the left of the 5 hundred; and find the whole amount or sum of money in the three bags to be 2,589 dollars.

From the above illustration, we obtain the following

RULE. Write the numbers, placing units under units, tens under tens, hundreds under hundreds, and draw a line under them.

Begin at the bottom of the column of units, and add all the figures in that column in succession: if the amount does not exceed nine, write it under the column; if the amount exceeds nine, write the right-hand figure of it under the column, and add the left-hand figure, or figures, with the figures in the next column.

Add the figures in each succeeding column in the same manner, and write down the whole amount of the last column.

[blocks in formation]

Two short parallel lines (=) indicate equality: thus, 100 cents; which is read, 1 dollar is equal

1 dollar = to 100 cents.

This cross (+) indicates addition: thus, 5+7-12; which is read, 5 plus 7 equal 12, or 5 and 7 equal 12. 13. What is the sum of 5,665 +6,545 +7,546 + 8,564 ?

14. What is the sum of 23,456 +34,567 +45,678 + 56,789 ?

15. What is the sum of 40,405 +50,604 +60,708+ 70,910 ?

16. What is the sum of 75,704 +85,406 95,115+

48,412?

17. What is the sum of 48,444 +57,555+ 66,333+

LESSON CXIX.

1. In a school 25 girls learn to write, 20 learn arithmetic, 18 learn grammar, 15 learn geography, and

12 learn history; what number of girls are there in the school?

2. There is an orchard in which there are 75 apple-trees,

25 peach-trees, 15 pear-trees, and 12 plum-trees;

what is the whole number of trees in the orchard? 3. There is a school in which there are 4 classes; in the first class there are 125 girls,, in the second 120, in the third 124, and in the fourth 175. What is the whole number of girls in the school?

4. A gardener has in his nursery 525 apple-trees, 375 peach-trees, 275 cherry-trees, 250 plum-trees, 175 pear-trees, and 750 other trees of various kinds; how many trees are there in the nursery?

5. In a certain farm there are 124 acres under cultivation, 75 acres for mowing, 140 acres of pasture, and 175 acres of wood-land; what number of acres are there in the farm?

6. A man purchased a farm for which he paid 5,750

dollars; he afterwards paid 375 dollars for clearing and fencing, and 325 dollars for barns and sheds. How many dollars did the farm cost him?

7. A mechanic owns five houses. No. 1 is worth 7,525 dollars; No. 2, 6,475 dollars; No. 3, 5,845 dollars; No. 4, 5,425 dollars; No. 5, 5,300 dollars. What number of dollars are the five houses worth?

8. A teacher wished to know how many questions had been performed by the first class in arithmetic during the last 5 weeks; and on inquiry, he found that the class had performed 75 questions during the first week, 85 during the second week, 95 during the third, 105 during the fourth, and 125 during the fifth week. How many questions had they performed during the last five weeks?

9. Three trains of cars started from Boston on the same

day; the first train carried 525 passengers, the second 675, and the third 750. How many passengers were there in the three trains?

LESSON CXX.

SUBTRACTION.

SUBTRACTION is the method of taking a less number from a greater, to find the remainder, or difference.

The less number is called the subtrahend, and the greater, the minuend.

The number found by taking a less number from a greater is called the remainder, or difference, and it shows how many the greater number exceeds the less.

Subtraction is performed, when each figure of the less number is smaller than the corresponding figure of the greater, by taking each figure of the less number from the corresponding figure of the greater, and writing the reremainder underneath; the several remainders will express the whole difference.

Illustration. A merchant purchased 765 yards of cloth, and has since sold 523 yards of it; what number of yards has he remaining unsold?

We first write down the greater number; then we

765 No. of yards purchased. 523 No. of yards sold. 242 No. of yards unsold. tens, and hundreds under units from 5 units, and 2 directly under the units. Then 2 tens from 6 tens, and 4 tens remain, which we write under the tens. Lastly, 5 hundred from 7 hundred, and 2 hundred remain, which we write under the hundreds. The whole remainder or difference is 242.

write the less number under the greater, placing units

under units, tens under hundreds. We then take 3 units remain, which we write

When any figure of the less number is larger than the corresponding figure of the greater number, the following question and its illustration will show the method of performing the operation :

A man borrowed 94 dollars, and has paid 46 dollars; how many dollars remain unpaid?

Borrowed 94 dollars.
Paid 46 dollars.

We cannot take 6 units from 4 units; and as 10 units of any lower order are equal to 1 unit

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