8. William earned 4 dollars in January, 6 dollars in February, 9 dollars in March, and 5 dollars in April. How much did he earn in these four months?

9. How many are 8 and 5? 18 and 5? 28 and 5? 38 and 5? 48 and 5? 58 and 5? 68 and 5? 78 and 5? 88 and 5? 98 and 5?

10. How many are 13 and 8? 23 and 8? 33 and 8? 43 and 8? 53 and 8? 63 and 8? 73 and 8? 83 and 8? 93 and 8?

11. How many are 27 and 9? 37 and 9? 47 and 9? 57 and 9? 67 and 9? 97 and 9?

12. Count by fours from 47 to 107. fives from 53 to 103.

Count by

22. The sum or amount of two or more numbers is a number which contains the same number of units as the two or more numbers together; thus, 5 is the sum of 2 and 3, because there are just as many units in 5 as in 2 and 3 together; for a like reason 10 cents is the sum of 1 cent, 3 cents, and 6 cents.

23. Only numbers of the same kind can be added; thus, 2 marbles and 3 marbles are 5 marbles; but 2 oranges and 3 marbles are neither 5 oranges nor 5 marbles.

24. Addition is the process of finding the sum of two or more numbers of the same kind.

25. A Sign is a mark which indicates an operation to be performed, or which is used to shorten some expression. Thus,

Instead of writing 3 and 5, we can write 3+ 5, read 3 plus 5. That is, the sign + (plus), written between two numbers, means the same as and.

=

Instead of writing 3 and 5 equals 8, we can write 35 8, read 3 plus 5 equals 8. That is, the sign, written between two numbers, or expressions, means equals.

Instead of writing dollars, we can write the sign $. Thus $6.25, means 6 dollars and 25 cents.

26. WRITTEN EXERCISES.

27. Find the sum of 4, 7, 5, and 3.

4

7

5

3

19, Ans.

As the most convenient way, we write the numbers in a column, as in the example. Beginning at the bottom we add, 3 (and 5 are) 8, (and 7 are) 15, (and 4 are) 19, and write the sum, 19, below.

In adding it is better not to name the numbers we are adding; thus, in Ex. 27, omit the words enclosed in parentheses in the explanation above, and say 3, 8, 15, 19.

33. Find the sum of the numbers in Ex. 28-32, beginning at the top and adding down the column.

NOTE. This second addition, if the result is the same, makes one conclude that the result is correct.

34. In one school there are 113 scholars, and in another 214. How many scholars are there in both? 35. July has 31 days, August 31 days, September 30 days, October 31 days, November 30 days, and December 31 days. How many days have these six months?

36. What is the sum of 203, 142, 313, and 121.

45. Add together 36, 78, and 349.

36

78

349 Ans. 463

Having written the numbers units under units, tens under tens, etc., we add the units, thus 9, 17, 23, or 2 tens 3 units. The 3 units we write under the units' column, and add the 2 tens to the tens in the tens' column, thus 2, 6, 13, 16 tens, or 1 hundred and 6 tens. The 6 tens we write under the tens' column, and add the 1 hundred to the hundreds in the hundreds' column, thus 1, 4 hundreds, which we write under the hundreds' column.

54. One field contains 8 acres, and another 79 acres. How many acres are there in both?

55. If one house has 32 windows, another 27 windows, and another 18 windows, how many windows have the three houses?

56. Thomas has 20 books, George has 19 books, Joseph has 15 books, and Daniel has 12 books. How many books have they all?

57. Mr. Adams paid 202 dollars for a horse, 57 dollars for a cow, and 74 dollars for some sheep. How much did he pay for all?

58. On one tree were 17 pears, on another 426, on another 302, and on another 213. How many pears were there?

59. One farmer has 643 sheep, another has 529, and another has 375. How many have they all?

60. Mr. Atwood has 393 dollars in the bank, Mr. Jones has 539 dollars, and Mr. Johnson has 615 dollars. How much have they in the bank?

61. A locomotive went 118 miles one day, 197 another, 236 another, and 183 another. How far did it go?

27. ORAL EXERCISES.

62. What is the sum of 5, 7, 9, 8, and 4?

63. A boy paid 18 cents for a top, 5 cents for a pencil, 6 cents for oranges, and 9 cents for writingpaper. How many cents did he pay for all?

64. A farmer sold 3 bushels of potatoes to one man, 17 to another, 5 to another, and 8 to another. How many bushels did he sell?

65. John collected for his father 8 dollars from one man, 6 dollars from a second, 3 dollars from a third, and 7 dollars from a fourth. How many dollars did he collect?

66. James paid 35 cents for an arithmetic, 8 cents for a writing-book, 5 cents for a lead-pencil, and 9 cents for ink. How many cents did he pay for all?

67. A grocer sold a pound of cheese for 11 cents, a pound of crackers for 10 cents, and a pound of sugar for 9 cents. How many cents' worth did he sell?

68. A farmer has 12 acres of corn, 6 acres of wheat, 4 acres of rye, and 3 acres of oats. How many acres of grain has he?

69. In a certain orchard there are 23 apple-trees,