B. This article contains the common multiplication table, as far as the product of the first ten numbers. The pupil should find the answers once or twice through, until he can find them readily, and then let him commit them to memory. 43. 6 times 3. In the third row count 6 times 3, and then ascertain their sum. 3 and 3 are 6, &c. 59. 7 times 9. In the ninth row count 7 times 9, or 7 rectangles, and ascertain their sum. 9 are 18, &c. 9 and C. This article is the same as the preceding, except in this the numbers are out of their natural order. D. In this article multiplication is applied to practical examples. They are of the same kind as those in article A of this section. 12. There are 8 times as many squares in 8 rows, as in 1 row. 8 times 8 are 64. 13. There are 6 times as many farthings in 6 pence, as in 1 penny. 6 times 4 are 24. 17. 12 times 4 are 48. Note. When a number is taken more than 10 times, as in the above example, after taking it 10 times on the plate, begin at the beginning of the row again, and take enough to make up the number. 23. There are 3 times as many pints in 3 quarts as in 1 quart. 3 times 2 are 6. And in 6 pints there are 6 times 4 gills or 24 gills. 28. In 3 gallons there are 12 quarts, and in 12 quarts there are 24 pints. 31. In 2 gallons are 8 quarts, in 8 quarts 16 pints; in 16 pints 64 gills. 16 times 4 are 64. 35. In one gallon are 32 gills; and 32 times 2 cents are 64 cents. Or, 1 pint will cost 8 cents, and there are 8 pints in a gallon. 8 times 8 are 64. 38. They will be 2 miles apart in 1 hour, 4 miles in 2 hours, &c. SECTION III, A. THIS section contains division. The pupil will scarcely distinguish it from multiplication. It is not important that he should at first. Though the pupil will be able to answer these questions by the maltiplication table, if he has committed it to memory thoroughly; yet it will be better to use the plate for some time. 9. As many times as 3 dollars are contained in 15 dollars, so many yards of cloth may be bought for 15 dollars. On plate I, in the third row, count fifteen and see how many times 3 it makes. It is performed very nearly like multiplication. B. In this article the pupil obtains the first ideas of fractions, and learns the most important of the terms which are applied to fractions.* The pupil has already been accustomed to look upon a collection of units, as forming a number, or as being itself a part of another number. He knows, therefore, that one is a part of every number, and that every number is a part of every number larger than itself. As every number may have a variety of parts, it is necessary to give names to the different parts in order to distinguish them from each other. The parts "As soon as the terms applied to fractions are fully comprehended, the operations on them are as simple as those on whole numbers. receive their names, according to the number of parts which any number is divided into. If the number is divided into two equal parts, the parts are called halves, if it is divided into three equal parts, they are called thirds, if into four parts, fourths, &c.; and having divided a number into parts, we can take as many of the parts as we choose. If a number be divided into five equal parts, and three of the parts be taken, the fraction is called three fifths of the number. The name shows at once into how many parts the number is to be divided, and how many parts are taken. The examples in this book are so arranged that the names will usually show the pupil how the operation is to be performed. In this section, although the pupil is taught to divide numbers into various parts, he is not taught to notice any fractions, except those where the numbers are divided into their simple units, which is the most simple kind. It will be best to use beans, pebbles, &c. first; and then plate I. 4. Show the pupil one of the rectangles in the second row, and explain to him that one is 1 half of 2. 7. In the second row count 3 units; it will take all the marks in the first, and 1 in the second rectangle. Consequently it is I time 2, and 1 half of another 2. 15. In the second row count 9. It will take all the marks in the four first rectangles, and 1 in the fifth. Therefore 9 is 4 times 2 and one half of another 2. 18. Show the pupil a rectangle in the third row, and ask him the question, and explain to him that 1 is 1 third of 3. 20. Since 1 is 1 third of 3, 2 must be 2 thirds of 3. 34. In the third row count 11. will take 3 Therefore rectangles and 2 marks in the fourth. 11 is 3 times 3, and 2 thirds of another 3. Proceed in the same manner with the other divisions. This being one of the most useful combinations, and one but very little understood by most people, especially when applied to large numbers, the pupil must be made perfectly familiar with it. Ask questions like those in the book for large numbers, and also some like the following: What part of 7 is 18? the answer will be 13. C. The first ten figures are here explained. They are used as an abridged method of writing numbers, and not with any reference to their use in calculating. This article is only a continuation of the last. All the numbers from 1 to 100 are introduced into the two articles, and are divided by all the numbers from 1 to 10; except that some of the largest are not divided by some of the smallest. 2. The pupil answers first, how many times 2 is contained in 12, then how many times 3. 45. 63 are how many times 5? In the fifth row count 63, It will take 12 rectangles and 3 marks in the 13th. It will be necessary to count once across the plate and begin again, and take 2 rectangles and a part of the third. 63 is 12 times 5 and 3 fifths of another 5. D. These examples, which are similar to those in article A of this section, are solved in the same manner. 5. It would take as many hours, as 3 miles are contained in 10 miles. 3 hours and of an hour. 20. They cost as many cents as there are 3 appies in 30 apples; that is, 10 cents. 21. 12 dollars a month: and 12 dollars a month is 3 dollars a week; that is, 18 shillings a week, which is 3 shillings a day. 26. The whole loss was 35 dollars, which was 7 dollars apiece. SECTION IV. A. THIS article contains multiplication simply. It is repeating a number a certain number of times and a part of another time. 14. 6 times 5 are 30, and 3 of 5 are 3, which added to 30 make 33. On the plate in the fifth row, take 6 rectangles and 3 marks in the seventh, and ascertain their sum. B. In this article the pupil is taught to change a certain number of twos into threes, threes into fives, &c. This article combines all the preceding oper ations. 24. 4 cords of wood will cost 28 dollars, and 4 of a cord will cost 2 dollars, which makes 30 dollars. 30 dollars will buy 3 hundred weight of sugar and of another hundred weight. 29. 7 times 8 are 56, and § of 8 are 5, which added to 56 make 61; 61 are 6 times 9, and 3 of 9. C. 1. 4 bushels of apples, at 3 shillings a bushel, come to 12 shillings; and 12 shillings are 2 dollars. 2. The two lemons come to 8 cents, and 8 cents will buy 4 apples, at 2 cents apiece. This is usually called Barter. The general principle is to find what the article will come to, whose price and quantity are given, and then to find how much of the other article that v will buy. |