Thomas said he performed 6 on Monday, 3 on Tuesday, and 5 on Wednesday. Each thought he had performed more than either of the others; so they quarrelled about it. Now, can you tell who had done the most? 5. Ella found 6 peaches under one tree, 5 under another, 3 under another, and enough to make up 20 under another. How many did she find under the last tree? 6. Augusta found 8 peaches under one tree, and 11 under another, after which she ate 2, gave her sister Martha 3, and distributed the rest among her playmates. How many did she distribute among her playmates? LESSON XXI. ADDITION AND SUBTRACTION. A. The question "How many are 6+9+7?" requires us to add 6, 9, and 7 together, that is, to find how many units there are in 6, 9, and 7, taken together. All such questions are questions in Addition. Addition is a process by which we find how many units there are in two or more numbers taken together. The number thus found is called the SUM or AMOUNT of the given numbers. Thus the sum of 6, 9, and 7 is 22, for 69+7=22. B. Add together or find the sum of 6, 8, and 3. Ans. 6 plus 8 are fourteen, plus 3 are 17. Hence the sum of 6, 8, and 3 is 17. Add together or find the sum of 9?" 1. 5, 8, and 7. 2. 3, 7, 4, and 4. 3. 2, 9, 3, and 5. 4. 2, 3, 4, 3, 2, and 1. 5. 6, 1, 5, 2, and 6. C. Such questions as "How many are 4 from "How many more are 17 than 8?" &c., are questions in SUBTRACTION. In the first, we are required to subtract 4 from 9, or to find how many units there are in the difference between 4 and 9, and in the second we are required to subtract 8 from 17, or to find how many units there are in the excess of 17 over 8. Hence Subtraction is a process by which we find how many units there are in the difference between two numbers, or in the excess of one number over another. LESSON XXII. 2 tens twenty, and is written 20, or 20. 3 tens= thirty, and is written 30, or 30. 7 tens 8 tens seventy, and is written 70, or 70. 9 tens ninety, and is written 90, or 90. 10 tens one hundred, and is written 100, or 100. = C. What number is equal to each of the following: A. A unit is a single thing, or one. 8 tens +7 units= eighty-seven = 87=87. 9 tens 9 units = ninety-nine = 99=99. B. Count from twenty to one hundred, thus:Twenty-one, twenty-two, twenty-three, &c., &c. How many are— NOTE.-An Oral Lesson, like the following, will be a good introduction to Multiplication. "If George should give me 2 apples, and then should give me 2 apples more, and then 2 more, how many times would he give me 2 apples?" "How many times 2 apples would he give me?" "How many apples?" "Then 3 times 2 apples are how many apples?" "How many then are 3 times 2?" "If William should give me 3 apples, and then should give me 3 apples more, how many times would he give me 3 apples ?" "How many times 3 apples would he give me?" "How many apples?" "How many then are 2 times 3?" most. 3 times 2, or 2 times 3?" "Which is the |