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2. of 18 are 24; 24 is 8 of 27; 27 is 5 times 5 and of 5.

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C. This article contains the multiplication table, in which the numbers from 10 to 20 are multiplied by the ten first numbers.

SECTION VIII.

Explanation of Plate II. Plate I., which has been used in the preceding sections, presents each unit as a simple object, and undivided. Plate II. presents the units as divisible objects, the different fractions of which form parts, and sums of parts, of unity.

This plate is divided into ten rows of equal squares, and each row into ten squares.

The first row is composed of ten empty squares, which are to be represented to the pupil as entire units. The second row presents ten squares, each divided into two equal parts by a vertical line, each of these parts, of course, represents one half. In the third row, each square is divided into three equal parts, by two vertical lines, each part repre. senting one third, &c., to the tenth row, which is die vided into ten equal parts, each part representing one tenth of unity.

N. B. In Plates II. and III., the spaces, and not the marks, are to be counted.

Be careful to make the pupil understand, Ist, that each squure on the plate is to be considered as an entire unit, or whole one. 2d, explain the divje sions into two, three, four, &c. parts. 3d, teach him to name the different parts. Make him observe that the name shows into how many parts one is divided, and how many parts are taken, in the same manner as it does when applied toʻlarger numbers. 4, for example, shows that one thing is to be divided into 7 equal parts, and 4 of those parts are to be taken. 4th, make the pupil compare the different parts together, and observe which is the largest. Ask him such questions as the following: Which are the smaller, halves or thirds ? Ans. Thirds. Why? Because the more parts a thing is divided into, the smaller the parts must be.

A. 15. On Plate II., count two squares in the second row, and then ascertain the number of spaces or halves in them. There are 4 halves.

21. In the 2d row, take 3 squares and 1 space in the 4th square; then count the spaces. Ans. 7 halves.

37. In the third row, take 5 squares, and 2 spaces an the 6th; then count the spaces or thirds. Ans. 17 thirds.

54. In the 5th row, take 6 squares, and 4 spaces in the 7th square; then court the spaces or fifths. Ans. 34 fifths.

B. 2. This operation is the reverse of the last. In the 2d row, count 4 spaces or halves, and see how many squares or whole ones it takes. It will take 2.

33. In the 9th row, count 48 spaces or 9ths, and see how many squares or whole ones it takes. It will take 5 squares and 3 spaces in the Oth. Ans. 5 wiole ones and .

SECTION IX.

A. 2. signifies that I thing is divided into 3 equal parts, and 1 part taken. Therefore 2 times. 1 third is 2 parts, or

6. 7 times ļ is , or 2.

10. On the plate in the 3d row, 5 times are 1, which takes 3 squares and I space. Ans. 34.

24. In the 9th row, take 4 spaces or 9ths, and repeat them 5 times, which will make 20, and will take 2 squares and 2 spaces. Ans. 27.

B. 4. 4 times 2 are 8, and 4 times I half are 4 halves, or 2, which added to 8 make 10.

18. 4 times 3 are 12, and 4 times are 12, or three whole ones, which added to 12 make 15.

32. 2 times 3 are 6, and 2 times are, which added to 6 make 6%.

40. 10 barrels of cider at 3 dollars and a barrel; 10 barrels at 3 dollars would be 30 dollars, then 10 times é is 5., or 8 and of a dollar. Ans. 382 dollars.

C. 2. if to each would be 3 times , or, which are 27 oranges.

3. V or 2 bushels.
4. 7 times are 41, or 54 gallons.
5. 8 yards and for 2 yards, that is, 10 yards.

6. 4 times 2 are 8, and 4 times are , or 2, which added to 8 make 104 bushels.

12. It would take 1 man 3 times as long as it would 3 men. Ans. 134 days.

14. 3 men would build 3 times as much as 1 man; and in 4 days they would build 4 times as much as · 1 day. Ans. 388 rods. '5. Ans. 12 yards.

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NOTE. The manner employed in example 40th is best for small numbers, and that in the 74th for large numbers.

B. 2. Ans. 1ę apiece. . 3. { of 3 is ? ; of a bushel apiece. 4. of 7 is 43; he gave away 41, and kept 24. 6. 1 half dollar a yard, or 50 cents.

7. } of 7 is , or 1%; of a dollar is of 100 cents, which is 40 cents. Ans, 1 dollar and 40 cents a bushel.

8. 4 of 8 is 1%. 4 of 100 is 332. Ans. 1 dollar and 33 cents; or it is 1 dollar and 2 shillings.

9. If 3 bushels cost 8 dollars, 1 bushel will cost 2 dollars and f, and 2 bushels will cost 51 dollars. Ans. 5 dollars and 2 shillings, or 332 cents.

13. If 7 pounds cost 40 cents, I will cost 55 cents; 10 pounds will cost 571 cents.

16. 1 cock would empty it in 6 hours, and 7 cock

would empty it in 4 of 6 hours, or of 1 hour, . which is of 60 minutes ; & of 60 minutes is 518 minutes.

SECTION XI. A. 2. 2 halves of a number make the number; consequently I and 1 half is the half of 2 times 1 and 1 half, which is 3.

15. 4is ļof 5 times 4 and 4, which is 221.
17. 4 is Ğ of 9 times 4*, which is 39%.
B. 4. 5 is 3 times of 5, which is {, or 14.

30. If 8 is of some number, f of Sis of the same number. of 3 is 24; 2 is of 4 times 2, which is 10%; therefore 8 is of 10%.

40. If 3 is 4, 6 of 8 is 7; of 8 is ; & is 4 of 5 cm, or 92 ; therefore 8 is of 92.

52. If & of a ton cost 23 dollars, of a ton must be of 23, that is, 4 dollars, and the whole would cost 9 times as much, that is, 415.

69. $ of 65 is 7* : 73 is į of 5 times 75, which is 364. 65 is of 365.

C. 4. 37 is g of 32, which taken from 37 leaves 44. Ans. 44 dollars.

5. 7 'feet must be 4 of the whole pole.

6. If he lost 4, he must have sold it for 7 of what it cost. 47 is of 604. Ans. 60 dollars and 42$ cents.

Miscellaneous Examples. 1. The shadow of the staff is of the length of the staff; therefore the shadow of the pole is of the length of the pole. 67 is of 83. Ans. 831 feet.

2. 9 gallons remain in the cistern in 1 hour. It will be filled in 10 hours and g; j of 60 minutes

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