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Ans. 9° 34' 54",

14. What is the difference of latitude between Boston and

Charleston?

15. Between Washington and London?
16. Between Philadelphia and Paris?
17. Between Quebec and St. Petersburg?
18. Between Portland and Cape Horn?†

19. Between Cape Horn and Cape Good Hope?
20. What is the difference of longitude between Boston and

Montreal?

21. Between New Orleans and New York?

22. Between Mexico and Paris?†

* From the American Almanac and New American Cyclopedia. †The difference of latitude between places on opposite sides of the equator is found by adding the latitudes. The difference of longigitude between places on opposite sides of the first meridian is found by adding the longitudes. If their sum exceeds 180°, the difference of longtude equals 360° minus that sum.

23. Between Constantinople and Chicago? 24. Between Canton and San Francisco?

For Dictation Exercises, see Key.

207. ADDITION AND SUBTRACTION OF DENOMINATE FRAC

TIONS.

ILL. EX., I. ewt. qr. what?

These fractions, being of different denominations, must first be reduced to the same denomination. The fraction cwt. may be changed to quarters, or the & qr. may be changed to parts of a cwt., and then addition can be performed. In the first case, the answer will be in qr. ; in the second, in cwt.

Another excellent method is first to reduce both fractions to integers of lower denominations, if necessary (Art. 198), and then add. Thus,

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EXAMPLES.

13s. 4d.
9

12 63, Ans.

Perform the following examples, and give the answers, as far as possible, in whole numbers of lower denominations.

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208.

MULTIPLICATION.

ILL. Ex. 1 pt. 3 gi. X 7 what?

OPERATION. pt. gi. 1 3

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7 × 3 gi.=21gi.=5pt.+1gi.; we write 1 gi. under gi. in the multiplicand, and reserve the 5 pt. to add with the pints in the product. 7x 1 pt. 7 pt., which with the 5 pt. reserved = 12 pt. 6 qt. 0 pt. Ans. 6 qt. 0 pt. 1 gi. 6 qt. O pt. 1 gi. Hence the

7

RULE FOR MULTIPLICATION of CompounD NUMBERS. Multiply the number of the lowest denomination by the multiplier, and divide the product thus obtained by the number it takes of that denomination to make one of the next higher; write the remainder under the term multiplied, and add the quotient with the product of the next higher denomination; and thus continue till all the terms of the multiplicand are multiplied,

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3. 20 T. 16 cwt. 4 lb. 15 oz. X 25 =?
4. 8 lb, 1 3, 6 3, 2 Đ, 18 gr. X 37 = ?
5. 24 lb. 8 oz. 16 pwt. 5 gr. X 78 = ?
6. 118° 24′52′′ × 55 = ?

7. 18 y. 37 d. 23 h. 14 min. 7 sec. X 12 = ?*

8. 36 y. 48 w. 5 d. 7 h. 3 m. 10 s. X 21=?*

9. 814 m. 21 ch. 45 l. X 83 = ?

10. 7 £. 6 s. 3 d. 2 qr. X 73 = ?

11. 4 m. 7 f. 35 rd. 3 yd. 2 ft. 11 in. × 29 = ? 12. 118 cd. 4 cd. ft. 1 cu. ft. X 35 = ?

13. 76 cu. yd. 12 cu. ft. 184 cu. in. × 24 =?

14. 4 sq. m. 320 A. 3 R. 25 sq. rd. 25 sq. yd. 7 sq. ft. 117 sq. in. X 9 = ?

15. How much land in 9 gardens each containing 34 sq. yd. 8 sq. ft. 67 sq. in. ?

rd. 4 sq.

* Art. 195, Note.

16. How many pickles in 17 jars, each jar holding 2 gall. 3 qt.

1 pt.?

17. If a car runs 18 m. 3 f. 29 r. 21 y. in of an hour, how far will it run in 7 h.?

For Dictation Exercises, see Key.

209. DIVISION.

ILL. EX. 17 cwt. 23 lb. 7 oz.

OPERATION. cwt. lb. Oz. 8) 17 23 7

2 15 67, Ans.

8

what?

of 17 cwt. 2 cwt. with a remainder of 1 cwt., which reduced to lbs. and added to the 23 lb. 123 lb.; } of 123 lb.15 lb. with a remainder of 3 lb., which reduced to oz. and added to the 7 oz. 55 Ans. 2 cwt. 15 lb. 67 oz. Hence the

Divide the

oz.; of 55 oz. — 67 oz. RULE FOR DIVISION OF COMPOUND NUMBERS. highest term of the dividend by the divisor; write down the quotient, and reduce the remainder to its value in the next lower denomination; add it to the number of that denomination, divide as before, and thus continue till every term is divided.

PROOF. Compound Division may be proved by Compound Multiplication, and Compound Multiplication by Compound Division.

EXAMPLES.

1. 14 £. 11 s. 3 d. 2 far. ÷ 8=? Ans. 1 £. 16 s. 4 d. 32 far. 2. 56 cd. 5 cd. ft. 14 cu. ft. ÷ 5 = ?

Ans. 11 cd. 2 cd. ft. 12 cu. ft. 691 in.

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5. 113 cu. yd. 22 cu. ft. 111 cu. in. ÷ 42 =?

6. 16 lb. 5 oz. 3 pwt. 21 gr. 13

7. 38 ib, 8 3, 7 3, 2 ǝ, 6 gr.÷15

?

:?

8. 27 T. 14 cwt. 2 qr. 16 lb. 12 oz. 3 dr. ÷ 6 = ?

9. 115 bu. 3 pk. 2 qt. 1 pt. 19 =?

10. 136 gall. 3 qt. 1 pt. ÷ 41 = ?

11. 1 m. 5 f. 37 r. 2 yd. 2 ft. 9 in. ÷ 12 =?

12. 365 A. 3 R. 19 sq. rd. 28 sq. yd. 4 sq. ft. 110 sq. in. 71=?

13. 30 y. 35 d. 7 h. 20 min. 35 sec. ÷ 29

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14. How far must a bird fly in one minute to fly 55 miles in an hour?

15. If 37 bu. 4 pk. of rye be divided between 7 men, what will each man receive?

16. If 65 A. 2 R. 18 sq. rd. 10 sq. yd. 14 sq. ft. be divided into 55 house-lots, what is the size of each?

17. How long will it take to travel 1 mile, at the rate of 75 miles in 10 h. 18 min. 12 s.?

18. Among how many men may 624 gall. 3 qt. be divided, that each man may receive 12 gall. 3 qt.?

NOTE. - Reduce each of the above to quarts before dividing.

19. How many bins, each containing 5 bu. 3 pk., will be required to hold 885 bu. 2 pk. of potatoes?

20. If a man walks 3 m. 6 fur. 26 rd. in one hour, how long will it take him to walk 23 m. 7 fur. 9 rd.?

that

For Dictation Exercises, see Key.

210. LONGITUDE AND TIME.

As the earth turns upon its axis once in 24 hours, it follows of 360°, or 15° of longitude, must pass under the sun in 1 of 15°, or 15', must pass under the sun in 1 min. of of 15', or 15," must pass under the sun in 1 sec. of

hour, and time, and

time; or, in a

TABULAR FORM.

15° of longitude make a difference of 1 hour in time.

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Hence, to find the difference of longitude between any two places: Multiply the difference of time between the two places, expressed in hours, minutes and seconds, by 15. The product will express the number of degrees, minutes and seconds required.

NOTE.

- As the earth turns from west to east, sunrise occurs earlier in places east and later in places west of any given point. Hence the time is later in all places east, and earlier in all places west, of any given point than it is at that point.

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