Review Problems 1. Through how many degrees of longitude does the sun seem to pass in an hour? Through how many minutes of longitude in a minute? Through how many seconds of longitude in a second? 2. If a man travels until his watch is 2 hours too fast, in which direction does he travel? Through how many degrees does he travel? 3. If a man travels until his watch is 2 minutes too slow, through how many minutes of longitude does he travel? 4. If the days are 2 hr. 20 min. longer than the nights, how long are the nights? 5. If the nights are 1 hr. 36 min. 10 sec. longer than the days, how long are the days? 6. If I buy cloth measured with a yardstick which is 2 inches too short, and pay 36 cents a yard, how much do I lose by the false measure in buying 20 yards? 7. If sugar is sold at the rate of 20 pounds for a dollar, but the scale indicates a pound for only 14 ounces, how many pounds are really sold for a dollar? 8. How much will it cost to have insurance placed upon 10,500 lb. of wool worth 36 cents a pound, for of its value, at %? 9. A man bought a house for $4000. He received $30 a month for rent, and paid $40 each year for repairs, and % of of its value for insurance. If the value of the property did not depreciate, how much had he gained for the use of his capital at the end of 4 years? 3% 10. At the end of 5 years the house was destroyed by How much did he gain or lose by the transaction? fire. The diagram represents a farm. It is drawn to the scale of of an inch to 10 rods. 1. Find how far it is from A to D by way of B and C. 2. Which is the nearer way from J to D, to follow the line by way of A and C, or by way of I and E? 3. If 2 acres were to be sold in the form of a rectangular strip taken from the east end of the farm, how many rods wide would the strip be? 4. If the rectangle CDE were completed by a continuation of the fences, how many acres would it contain? 5. If the rectangle JIH were completed, how many acres would it contain? 6. If the rectangle AJI were completed, how many acres would it contain? 7. If the fence CB were continued across the farm, how many acres would there be in the part east of the fence? 8. Find how many acres there are in the whole farm. 9. If the fence IH were continued across the farm so as to convert the west end of the farm into a pasture, how many cows could be pastured in it, if each cow must have at least 2 acres? Standard Time In traveling from west to east or from east to west, since the true time as determined by the sun constantly changes, a watch becomes too slow or too fast. To avoid the confusion which would result from this, it is agreed in the United States to set the clocks so that there shall be only three changes of a whole hour each in passing across the country. The country is divided into four sections. All the people of any one of these sections set their clocks and watches at what would be the true time for the circle of longitude that passes through the middle of the section. The circles adopted as standards are 15° apart, as indicated upon the map on p. 26. 1. At 5 o'clock, what time is it at a place which is 30° farther east? 2. What time is it at a place 45° farther west? 3. According to standard time, when it is noon in New York, what time is it in California? (Consult the map.) 4. When it is 8 A.M. in Colorado, what time is it in New Jersey? 5. When it is 1 P.M. in Wisconsin, what time is it in Oregon ? 6. How should a watch be changed in going across central Nebraska from the western to the eastern part? in going from Massachusetts to Montana? 7. How much difference is there between the true time and the standard time at a place whose longitude is 80° W.? The standard time for the place is the true time for longitude 75° W. What time corresponds to 5° of longitude? 8. What is the difference between the true time and the standard time, at a place whose longitude is 85° W.? 971 W.? 118° 30′ W.? 94° 45′ W.? |
