There are 3 fields, which measure as follows, viz. 17A. 3r. 16 p.; 28 A. 5 r. 18 p.; 11 A. Or. 25 p.; how much land in the three fields?

A merchant bought two casks of brandy, containing follows, viz. 70 gal. 3 qts.; 67 gal. 1 qt.; how many hogsheads, of 63 gal. each, in the whole?

SUBTRACTION

OF COMPOUND NUMBERS.

39. 1. A boy bought a knife for 9 cents, and sold it for 17 cents; how much did he gain by the bargain?

2. A boy bought a slate for 2 s. 6 d., and a book for 3 s. 6 d. ; how much more was the cost of the book than of the slate? 3. A boy owed his playmate 2 s.; he paid him 1 s. 6 d.; how much did he then owe him?

4. Bought two books; the price of one was 4 s. 6 d., the price of the other 3 s. 9 d.; what was the difference of their

costs?

5. A boy lent 5 s. 3 d.; he received in payment 2 s. 6 d.; how much was then due ?

6. A man has a bottle of wine containing 2 gallons and 3 quarts; after turning out 3 quarts, how much remained? 7. How much is 4 gal. less 3 gal. ? 4 gal. (less) 2 qts.? 4 gal. - 1 qt.? 4 gal. 1 gal. 1 qt.? 4 gal. —1 gal. 2 qts.? 4 gal. 1 gal. 3 qts.? 4 gal. 2 gal. 3 qts.? 4 gal. i qt.

-

1 gal. 3 qts.?

8. How much is 1 ft.

3 in.

10 in. ?

1 ft. 6 in.? 7 ft. 8 in. - 4 ft. 2 in.? 7 ft. 8 in. 5 ft.

9. What is the difference between 4£. 6 s. and 1£. 8 s. ? 10. How much is 3£. (less) 1 s. 3£.

2 s.? 3£.

3 s.? 3£. 15 s.? 3. 4 s. -2£. 6 s.? 10£. 4 s. 5£. 8. s?

11. A man bought a horse for 30£. 4 s. 8 d., and a cow for 5£. 14 s. 6 d. ; what is the difference of their costs?

OPERATION.
£. S. d.

Minuend, 30 4 8
Subtrahend, 5 14 6

Ans. 24 10 2

As the two numbers are large, it will be convenient to write them down, the less under the greater, pence under pence, shillings under shillings, &c. We may now take 6 d. from 8d., and there will remain 2 d. Proceeding to the shillings, we cannot take 14 s. from 4 s., but we may borrow, as in simple numbers, 1 from the pounds, 20 s., which joined to the 4 s. makes 24's., from which taking 14 s. leaves 10 s., which we set down. We must now carry 1 to the 5£., making 6 £., which taken from 30£. leaves 24£., and the work is done. Note. The most convenient way in borrowing is, to subH*

tract the subtrahend from the figure borrowed, and add the difference to the minuend. Thus, in the above example, 14 from 20 leaves 6, and 4 is 10.

The process in the foregoing example may be presented in the form of a RULE for the Subtraction of Compound Num

bers:

I. Write down the sums or quantities, the less under the greater, placing those numbers which are of the same denomination directly under each other.

II. Beginning with the least denomination, take successively the lower number in each denomination from the upper, and write the remainder underneath, as in subtraction of simple numbers.

III. If the lower number of any denomination be greater than the upper, borrow as many units as make one of the next higher denomination, subtract the lower number therefrom, and to the remainder add the upper number, remembering always to add I to the next higher denomination for that which you borrowed.

Proof. Add the remainder and the subtrahend together, as in subtraction of simple numbers; if the work be right, the amount will be equal to the minuend.

EXAMPLES FOR PRACTICE.

1. A merchant sold goods to the amount of 136 £. 7 s. 64 d., and received in payment 50£. 10s. 44d; how much remained due? Ans. 85. 17 s. 1 d. 2. A man bought a farm for 1256 £. 10 s., and, in selling it, lost 87. 108. 6 d.; how much did he sell it for? Ans. 1168£. 19 s. 6 d. 3. A man bought a horse for 27£. and a pair of oxen for 19£. 12 s. 8d.; how much was the horse valued more than the oxen?

4. A merchant drew from a hogshead of molasses, at one time, 13 gal. qts.; at another time, 5 gal. 2 qts. 1 pt.; what quantity was there left? Ans. 43 gal. 2 qts. 1 pt. 5. A pipe of brandy, containing 118 gal. sprang a leak, when it was found only 97 gal. 3 qts. I pt. remained in the cask; how much was the leakage?

6. There was a silver tankard which weighed 3 lb. 4 oz. ; the lid alone weighed 5 oz. 7 pwt. 13 grs.; how much did the tankard weigh without the lid ?

7. From 15 lb. 2 oz. 5 pwt. take 9 oz. 8 pwt. 10 grs.

8. Bought a hogshead of sugar, weighing 9 cwt. 2 qra 17 lb.; sold at three several times as follows, viz. 2 cwt. 1 qr. 11 lb. 5 oz.; 2 qrs. 18 lb. 10 oz.; 25 lb. 6 oz.; what weight of sugar which remained unsold?

I was the

Ans. 6 cwt. 1 qr. 17 lb. 11 oz. 9. Bought a piece of black broadcloth, containing 36 yds. 2 qrs.; two pieces of blue, one containing 10 yds. 3 qrs. 2 na., the other, 18 yds. 3 qrs. 3 na.; how much more was there of the black than of the blue?

10. From 28 miles, 5 fur. 16 r. take 15 m. 6 fur. 26 r. 12 ft. 11. A farmer has two mowing fields; one containing 13 acres 6 roods; the other, 14 acres 3 roods: he has two pastures also; one containing 26 A. 2 r. 27 p.; the other, 45 A. 5 r. 33 p.: how much more has he of pasture than of mowing?

12. From 64 A. 2 r. 11 p. 29 ft. take 26 A. 5 r. 34 p. 132 ft. 13. From a pile of wood, containing 21 cords, was sold, at one time, 8 cords 76 cubic feet; at another time, 5 cords 7. cord feet; what was the quantity of wood left?

14. How many days, hours and minutes of any year will be future time on the 4th day of July, 20 minutes past 3 o'clock, P. M. ? Ans. 180 days, 8 hours, 40 minutes. 15. On the same day, hour and minute of July, given in the above example, what will be the difference between the past and future time of that month?

16. A note, bearing date Dec. 28th, 1826, was paid Jan. 2d, 1827; how long was it at interest?

The distance of time from one date to that of another may be found by subtracting the first date from the last, observing to number the months according to their order. (¶ 37.)

17. A note, bearing date Oct. 20th, 1823, was paid April 25th, 1825; how long was the note at interest?

18. What is the difference of time from Sept. 29, 1816, to April 2d, 1819 ? Ans. 2 y. 6 m. 3 d. 19. London is 51° 32', and Boston 42° 23′ N. latitude; what is the difference of latitude between the two places?

Ans. 9° 9

20. Boston is 71° 3', and the city of Washington is 77° 43' W. longitude; what is the difference of longitude between the two places? Ans. 6° 40'. 21. The island of Cuba lies between 74° and 85° W. lon gitude; how many degrees in longitude does it extend?

40. 1. When it is 12 o'clock at the most easterly extremity of the island of Cuba, what will be the hour at the most westerly extremity, the difference in longitude being 11° ?

Note. The circumference of the earth being 360°, and the earth performing one entire revolution in 24 hours, it follows, that the motion of the earth, on its surface, from west to east, is

15° of motion in 1 hour of time; consequently,

1° of motion in 4 minutes of time, and

1' of motion in 4 seconds of time.

From these premises it follows, that, when there is a dif ference in longitude between two places, there will be a corresponding difference in the hour, or time of the day. The difference in longitude being 15°, the difference in time will be 1 hour, the place easterly having the time of the day 1 hour earlier than the place westerly, which must be par ticularly regarded.

If the difference in longitude be 1°, the difference in time will be 4 minutes, &c.

Hence,-If the difference in longitude, in degrees and minutes, between two places, be multiplied by 4, the product will be the difference in time, in minutes and seconds, which may be reduced to hours.

We are now prepared to answer the above question.

11°
4

44 minutes.

Hence, when it is 12 o'clock at the most easterly extremity of the island, it will be 16 minutes past 11 o'clock at the most western extremity.

2. Boston being 6° 40′ E. longitude from the city of Washington, when it is 3 o'clock at the city of Washington, what is the hour at Boston?

Ans. 26 minutes 40 seconds past 3 o'clock. 8. Massachusetts being about 72°, and the Sandwich Islands about 155° W. longitude, when it is 28 minutes past 6 o'clock, A. M. at the Sandwich Islands, what will be the hour in Massachusetts ? Ans. 12 o'clock at noon.