Εικόνες σελίδας
PDF
Ηλεκτρ. έκδοση

319. What cost 15 cd. 13 cu. ft. of wood, at $4.63 per cord?

320. What are the contents of a pile of wood 9 ft. 33 in. long, 4 ft. 3 in. wide, and 8 ft. 7 in. high?

321. At $9.37 per cord, what will a pile of wood cost that is 8 ft. 2 in. long, 5 ft. 23 in. wide, 8 ft. 11 in. high?

QUESTIONS.-HOW are common fractions changed to decimals? (180., a.) What is the difference between changing common fractions to decimals and the division of decimals? (180., a.) How may the operation be proved? (180., b.) When the denominator of a fraction contains other factors than 2 or 5, will the division be exact? (180., c., 1.) When a figure or figures are continually repeated, what are they called? (180., c., 2.)

LESSON XXXII.

322. What are the contents of a board 12 ft. 6 in. long, and 2 ft. 9 in. wide?

323. What are the contents of 369 boards, each 12 ft. 8 in. long, 3 ft. 2 in. wide?

324. What would be the cost of a load containing 53 boards, each board 13 ft. 2 in. long, 73 in. wide, at 24 cts. per square foot?

325. Bought 13 casks of vinegar, each containing 25 gal. 3 qts. 1 pt., at $0.375 per gallon; what was the cost?

326. Bought a farm containing 143 A. 304 sq. rds., at $46.43 per acre; what was the cost?

327. Paid $14.53 for 2.37 cwt. of nails; how much was that per pound?

328. Paid $17.28 for 25 cwt. of nails; how much was that per pound?

329. Paid $25.17 for 3.72 cwt. of sugar; how much was that per pound?

330. Paid $36.42 for 43 cwt. of sugar; how much was that per pound?

331. Bought 14.32 cwt. of hay at $0.05 per pound; how much did it cost?

QUESTIONS.-How are circulating decimals distinguished? (180., c., 3.) How are repetends changed to common fractions? (180., c., 4.) What is reduction descending in denominate decimals? (181.) What is reduction ascending? (182.) Give the analysis of an example of reduction descending. (182., a.) reduction ascending. (182., b.)

Give the analysis of an example of

LESSON XXXIII.

332. Bought 2.42 cwt. of flour at $1.25 per qr., and sold it at 6.5 cts. per pound; how much did I gain?

333. Bought 94 qr. of rice at 7 cts. per pound, and sold it for 11 cts. per pound; how much did I make by the operation?

334. Bought 4.3 hhd. of wine at $2.14 per gallon, and sold it at 12.24 cts. per gill; how much did I make by the operation?

335. What will of an ounce of snuff cost, at $1.53 per pound?

336. What will oz. of hay cost, at $13.20 per ton? 337. What will .341 of a grain of gold be worth, at $16. per ounce?

338. What will of a grain of gold be worth, at $238 .46 per pound?

339. If of a cord of wood cost $6.50, what will one cord cost?

340. If of a cord of wood cost $8.72, what will 9.34 cords cost?

341. If of a cord of wood cost $9.37, what will be the

[ocr errors]

cost of a pile of wood 16 ft. 8 in. long, 3 ft. 7 in. wide, and 7 ft. 3 in. high?

QUESTIONS.-Write on the blackboard a rule for reducing a common fraction to a decimal. (180., a.) Write a rule in the same manner for reducing a decimal to a common fraction. (180., b.) What is the difference between a common and a decimal fraction? ·(124.} (125.) How many tenths make a unit? How much larger is a hun dred than a tenth? A ten than a hundredth ?

LESSON XXXIV.

342. A man bought a ship for $35000; % of it was sold to Mr. Jones for $22314.23, and the remainder to another man at a gain of $416.82; what was made on the sale of the ship?

343. A man bought a ship for $25000; .75 of it was sold to Mr. Mead for $21037.42, and the remainder to Captain Read, at a gain of 33 cts. on each dollar of the cost of the remainder; how much was made on the sale of the ship?

344. A man had 2 bu. 2 pks. 4 qts. of oats; he sold 3 pks. 7 qts. 1 pt.; what decimal part of his oats did he sell?

345. Having 9.34 A. of land, I sold 3 A. 1 R. 18 sq. rds.. what decimal part of the whole did Į have left?

346. Having 5 A. 2 R. 17 sq. rds. of land, I sold 3 A. 1 R. 14 sq. rds.; what decimal part of the land did I sell? 347. At $1.25 per yard, how many yards of cloth can I buy for $3.72?

348. At $1.21 per yard, how many yards of cloth can I buy for $0.003 ?

349. At 38.22 cts. per bushel, how many bushels of oats can I purchase for $0.02?

350. At 483 cents per bushel, how many bushels of oats can I purchase for $4.37?

351. If you pay .375£. for 41 bbls. of cider, how much do you pay per gill?

352. At £.25 per yard, what will be the cost of 13 pieces of cloth, each piece containing 393 yds. 1 qr.?

353. Paid £. for .625 of a yard of sarcenet; what was that per yard?

354. Paid § of a dollar for .125 bbls. of flour; how much was that per barrel?

355. Bought .37424 A. of land, at $.5 per foot; what did it cost?

356. Bought .673 ton of iron, and sold 1 qr. 13 lbs. to Mr. O. H. Gager; how much was the remainder worth, at 2s. 6d. per pound?

QUESTIONS.-How much larger is a unit than a thousandth? A ten than a ten thousandth? A thousand than a thousandth? If tens are multiplied by tenths, what will be the denomination of the product? (177.) If tens are multiplied by hundredths? By units? By ten thousandths? By millionths? By tens? If tenths are divided by hundredths, what will be the denomination of the quotient? (179.) What is the general law? (179., e.) Thousandths divided by tenths gives what denomination: By tens? By thousandths? By ten thousandths?

LESSON XXXV.

PER CENTAGE.

183. Per centum, or its abbreviation, per cent., is a term which signifies by the hundred; hence, 3 pounds gain on 100 pounds is said to be a gain of 3 per cent., or of 3 hundredths of a pound on one pound.

8 gallons loss on 100 gallons is said to be a loss of 8 per cent., or of 8 hundredths of a gallon on one gallon, &c.

MENTAL EXERCISES.

1. At a gain of 3 pounds on 100 pounds, how much is gained on 7 pounds?

ANALYSIS.-(1.) If the profit on 100 pounds is 3 pounds, the profit on one pound will be 1 hundredth of 3 pounds, which is three hundredths (.03) of one pound.

(2.) If the profit on one pound is .03 of a pound, the profit on 7 pounds is 7 times .03 of a pound, which is .21 of a pound. Therefore, 3 per cent of 7 pounds is .21 of a pound.

2. I lose 9 gallons on 100 gallons; how much is my on 12 gallons?

loss

3. If I receive $4 interest on $100 for one year, how much do I receive on $12 for the same time?

4. What is 9 per cent. of 7 quarts?

ANALYSIS.-9 per cent. signifies 9 quarts on 100 quarts,` or Too of a quart on one quart.

If 9 per cent. of one quart is .09 of a quart, then 9 per cent. of 7 quarts is 7 times .09 of a quart, which is .63 of a quart. Therefore, 9 per cent. of 7 qts. is .63 of a quart.

5. What is 12 per cent. of 11 ounces? of 8 pks.? of $10? of 8 pounds?

6. What is 7 per cent. of 12 days? of 9 pks.? of 8 bushels? of 11 ounces?

7. If I lose 9 farthings on 100 farthings, what per cent. do I lose?

8. If I lose 17 ounces on 100 ounces, what per cent. do I lose?

9. If by investing $100 I gain $13, what per cent. do I gain?

10. I bought a horse for $100, and sold it for $15 more than I gave for it; how much did I gain per cent.?

11. I bought a house for $100, and sold it for $125.; how much did I gain per cent.?

QUESTIONS.-What is a unit? (1.) What is the difference between a unit and a number? (1.) (2.) What is the difference between an

« ΠροηγούμενηΣυνέχεια »