7. Three hundred two thousand seventy-six, two hundred thousand sixteen, one hundred eighteen thousand six hundred.

8. Four hundred forty-four thousand four hundred forty-four, six hundred thousand six, nine hundred thousand.

9. Seven hundred thousand, two hundred thousand two hundred two, five hundred fifteen thousand five hundred.

10. Six hundred seventy thousand seventy, three hundred thirty thousand seven hundred, seven million two hundred.

11. Three million eighty-one thousand, nine million five hundred thousand, twelve million fifty-three.

12. Ten million ten thousand ten, twenty-seven million four hundred thousand eleven, eighty-nine million eight hundred six thousand forty-seven.

13. Three hundred million three hundred, five hundred seven million three hundred thousand nine.

14. Nine hundred ninety-seven million three thousand fourteen, one billion three hundred million, five billion one hundred fifty-four, thirteen billion four hundred six thousand.

15. Three hundred eighteen billion one million, six hundred three billion, eight hundred thirty-one billion eighty thousand.

16. Four trillion, thirty-seven trillion sixty-four thousand, four hundred five trillion two million, nine quadrillion nine billion nine.

NOTE: Begin at the left hand every time.

ADDITION.

33. 1. Henry caught 4 trout and Albert caught 3. How many trout did both boys catch?

2. In my garden are 5 cherry trees and 3 pear trees. How many trees are there in my garden?

3. A farmer sold a sheep for 6 dollars and a pig for 4 dollars. How many dollars did he receive for both?

4. Ella practiced her music for 6 hours yesterday and 5 hours to-day. How many hours has she practiced in 2 days?

5. In a certain class are 6 boys and 7 girls. How many children are there in the class?

6. A father gave to one of his children 5 cents, to another 3 cents, and to another 6 cents. How many

cents did he give to all three of them?

7. How many are 3 oranges, 5 oranges, 4 oranges, and 2 oranges?

What do you call the work you have been doing?

34. Addition is the finding of a number which shall contain as many ones as two or more numbers taken together.

The number found is called the sum of the other numbers.

The sign means and; the sign = means are, or equal.

Read: 7 plums + 4 plums = 11 plums; 8 cents + 9 cents = 17 cents.

Can you tell how many 3 apples and 4 cows are? Why not?

Only units of the same kind can be added.

35. Combinations of Two Numbers.-There may seem to be a very great number of possible combinations of two numbers in addition, but they are all given in the following tables. How many are there?

These forty-five combinations of the tables include all that are necessary to any addition whatever. The addition of large numbers is no more difficult than the addition of these small ones. In adding fifty-six and eight, for instance, we have simply to add the six and eight. According to the tables, their sum is one ten and four, or fourteen; hence, the result will be six tens and four, or sixty-four. The sum of seventy and twenty is simply the sum of seven tens and two tens. These illustrations show that the tables contain all the combinations we need to make, in the separate steps of any addition. For this reason the tables ought to be thoroughly committed to memory. It must be done before any real progress in addition is possible.

ADDENDS.

36. Order of Addends.- Although there are only forty-five combinations, in all but nine of them the numbers to be added may occur in two orders, thus: 6+5=11; 5+6=11; 7+8=15; 8+7=15, etc.

The orders in which the forty-five combinations may occur are promiscuously given below in two forms. Practice upon them until you can name each sum the instant your eye rests upon the two figures that represent the numbers to be added: