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367. 1. How many grains in 3 pwt.? In 5?

110 oz.?

2. How many ounces in 60 pwt.? In 100 pwt.? 120 pwt.? 3. How many ounces in 5 lb.? In 3 lb. 10 oz.? 4 lb.? 4. How many ounces in 40 drams? In 64 dr.? 120 dr.? 5. How many pounds in 36 oz.? In 70 oz.? 6. How many scruples in 10 drams? In 80 grains? 7. What will a gold chain, weighing 1 oz. 12 pwt., cost at $1 a pennyweight?

8. What part of a pound Troy are 4 oz.? 6 oz.? 8 oz.? 9. How many parts of pure gold in a ring 16 carats fine? 10. How many powders of 8 grains each, can be made from half an ounce of medicine?

11. How many tablespoons, each weighing 2 oz., can be made from 2 lb. 10 oz. of silver?

12. How many pills of gr. 5 each can be made from 31 2 of calomel ?

13. What is the value of a gold bracelet weighing 3 oz. 15 pwt., at $20 an ounce ?

14. How many ounces in 4 lb. Avoir.? In 5 lb. 6 oz.? 15. How many pounds in 7 cwt.? In 84 cwt. ? 16. How many cwt. in 600 lb.? In 350 lb.? In 875 lb.? 17. In 3 T., how many hundred-weight? How many lb.? 18. What part of a cwt. are 25 lb.? 50 lb.? 75 lb.? 19. How many cwt. in of a ton? In of a ton? 20. How many tons are 50 cwt.? 21. What will a ton of hay cost, at 1 cent a pound? 22. At 8 cents an ounce, what will 24 lb. of licorice cost? 23. What will lb. of candy cost, at 3 cents an oz.? 24. At $2 a bushel, what must be paid for 2 bags of wheat, each containing 120 lb. ?

80 cwt.? 95 cwt.?

368.

SYNOPSIS FOR REVIEW.

1. DEFINITIONS.

1. Denominate Number. 2. Simpie

{ Number. 3. Comp. Denom. Number

1. DEFINITION OF MEASURE.

2. CLASSIFICATION.

1. LINEAR MEAS

URE.

1. For what used.

2. Table.

3. Other Denominations.

4. Surveyors' Linear Meas.

1. For what used.

1. Surface.

2. SQUARE MEAS

URE.

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5.MEAS.OF W'GHT. 4.MEAS. OF CAPAC'Y. 3. MEASURES OF EXTENSION.

2. Defs. 2. Area.

3. Square.

3. Table.

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MEASURES OF TIME.

369. Time is a measured portion of duration. 370. The Unit of measure is the mean solar day.

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In most business transactions 30 days are considered a month, and 12 months a year. Four weeks are sometimes called a lunar month. The calendar year is divided as shown in the diagram:

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3. The Civil Day, used for business purposes and which corresponds with the mean solar day,begins and ends at 12 o'clock, midnight. t. A.M. de

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IST Mo. 2ND MO.

365 or 366 days.

notes the time before noon; M., at noon; and P.M., afternoon.

4. The Solar Year is exactly 365 da. 5 hr. 48 min. 49.7 sec.

5. The Common Year consists of 365 da. for 3 successive years, every fourth year containing 366 da., one day being added for the excess of the solar year over 365 da. This day is added to the month of February, which then has 29 da., and the year is called Leap-year.

371. The following rule for leap year will render the calendar correct to within 1 day, for a period of 4000 years

I. Every year exactly divisible by 4 is a leap year, the centennial years excepted; the other years are common years. Thus, 1876 is a leap year, but 1877 is a common year.

II. Every centennial year exactly divisible by 400 is a leap year; the other centennial years are common years. Thus, the year 2000 is a L. year, but 1800 and 1900 are com. years.

CIRCULAR MEASURE.

372. Circular or Angular Measure is used in measuring angles and arcs of circles, in determining latitude and longitude, the location of places and vessels, etc.

373. The Unit is the Degree, which is the circumference of any circle.

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377. An Angle is the difference in the direction of two lines proceeding from a common point called the vertex. Thus, ACD and D C B

are angles, and C is their vertex.

378. A Right Angle is

formed by drawing one line perpendicular to another. Thus, ACE and ECB are right angles. A

FIG. 2.
E

B

379. A Degree is one of the 360 equal parts into which the circumference of a circle is supposed to be divided. Thus, E and B (Fig. 1) are at the distance of 90°, or a right angle from each other, the vertex being at the center of the circle.

380. The Measure of an Angle is the arc of the circle included between its sides. Thus, the arc D B (Fig. 3) is the measure of the angle D C B.

FIG. 3.

B

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1. A Semi-Circum, is one-half of a circumference, or 180°. 2. A Quadrant is one-fourth of a circumference, or 90°. 3. A Sextant is one-sixth of a circumference, or 60°.

4. A Sign is one-twelfth of a circumference, or 30°.

60

5. A degree varies with the size of the circle; thus, a degree of long. at the Equator is 69.16 statute miles, at 30° of latitude it is 59.81 mi., at 60° of latitude it is 34.53 mi., and at 90°, it is nothing. 6. A minute of the earth's circumference is called a geographic, or nautical mile, and is a small fraction less than 1.16 common miles.

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