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11. 5 by 80.
18. 144.375 by 16.5.
Exercise 91. Applied Problems in Decimals
1. A barrel holds 31.5 gallons. How many bottles holding .125 of a gallon can be filled from a barrel of vinegar?
2. A knot is the unit of measure in estimating the speed of ships. It is equal to 1.15 miles. The battleship Pennsylvania made 21.05 knots per hour in its trial speed test. Express the speed of this battleship in miles per hour.
3. The torpedo boat destroyer Jouett made 32.27 knots per hour in its trial speed test. How many miles per hour is that record?
4. A passenger train, on a 180.5-mile run, made an average speed of 42.5 miles per hour. How long did it take the train to make the run?
5. At that rate how far would the train go in 2.25 hours?
6. A touring car was driven 82.5 miles on 5 gallons of gasoline. What was the average distance obtained from a gallon of gasoline?
7. A bushel is equal to 1.25 cubic feet. How many bushels will a bin hold whose volume is 162.5 cubic feet?
8. The railroad fare between two cities is $2.46. The rate between these cities is $.03 cents a mile. Find the distance between the cities.
9. A square rod is equal to 30.25 square yards. How many square rods are there in a plot of ground containing 931.5 square yards?
10. A rod=162 feet. How many rods long is a garden plot 330 feet long?
11. Jack sold a grocer 12 cabbages which weighed 28.5 pounds. What was the average weight of the cabbage?
12. A cubic foot of water weighs 62.5 pounds. Ice weighs only .92 as much as water. How much does a cubic foot of ice weigh?
13. Gasoline weighs only .76 as much as water. How much does a cubic foot of gasoline weigh? There are 7.5 gallons in a cubic foot. How much does a gallon of gasoline weigh?
14. The distance from New York to Chicago is 952 miles. How long will it take a train to go from New York to Chicago at an average speed of 36.75 miles per hour?
15. The record for the 100-yard dash for a high-school meet was 10.8 seconds. The record in a grammar-school meet was 12.2 seconds. How many seconds shorter was the high-school record?
16. The English shilling is worth $.243375 in our money. How much is 8 shillings worth in our money?
17. A cubic foot of water weighs 62.5 pounds. How much does a barrel, 4.2 cubic feet, of water weigh?
18. A cubic foot of iron weighs about 465 pounds. How many cubic feet of iron weigh a ton?
19. A rectangular field is 24.75 rods long and 15.625 rods wide. How many rods of wire fence will it take to enclose the field?
20. Find the length of the four sides of a rectangle that is 7.5 inches long and 5.625 inches wide.
21. Find the cost of 2.75 yards of toweling at $.89 a yard.
22. Arthur sold 4.5 dozen eggs to a grocer at 41 cents a dozen. If he bought groceries amounting to $2.38, how much cash did he give in the exchange?
23. A sixth-grade class of 28 pupils went on a picnic. The total expenses amounted to $7.56. How much was each one's share, if they divided the expenses equally?
24. A farmer sent 2460 pounds of milk during one week to a condensary. It cost him 15 cents per cwt. to have it hauled. How much did he pay for the hauling?
25. The condensary paid the farmer $3.55 per cwt. for the 2460 pounds of milk. What did he receive for the milk? How much did he have left after paying for the hauling?
26. In a certain kind of bronze .925 of the metal is copper, .07 is tin and .005 is phosphorus. How many pounds of copper in 50.5 pounds of the bronze? How much tin? How much phosphorus?
27. A passenger train made a run of 235.6 miles in 5.4 hours. What was its average speed per hour?
28. How much does a cubic foot of water weigh? (See preceding page.) How many pounds will the water weigh in a tank holding 45.25 cubic feet?
29. How many feet are there in a rod? How many rods long is a field which measures 825 feet in length?
30. The product of two numbers is 255.15 and one of the numbers is 18.9. What is the other number?
31. A farmer sold 4 loads of corn which averaged 32.6 bushels per load for $1.27 per bushel. How much did he receive for the 4 loads?
Exercise 92. Wireless The Navy Department makes extensive use of wireless for giving orders to the vessels of our navy when they are at sea. The central wireless station is located at Radio, Virginia, and is generally called the Arlington Radio Station.
The Arlington station has three skeleton towers, one 600 feet high and two each 450 feet high. Five hundred tons of steel were used in the construction of the highest tower and 275 tons in each of the smaller towers. Why is it necessary to have such high towers to send wireless messages?
1. How many tons of steel were used in the three towers of the Arlington Radio Station?
2. How much did the steel cost for the three towers at $56.20 per ton?
3. The distance from Arlington to the wireless station in Darien is 1779 miles. The distance to the Great Lakes Station (shown in the illustration) is 1000 miles. How much
farther is it to Darien than to the
4. In the 12 months ending June
5. In January, 1916, the Arlington Station handled 6189 messages. What was the average per day during that month? How many messages did this station send per hour?
The Great Lakes Wireless Station
Exercise 93. Changing Common Fractions to Decimals 1. How do you change a common fraction to a decimal?
2. Give the equivalent decimals for the following common fractions: 1, 1, 1, }, }, }, }, 5, 3, 5, ž.
It is often more convenient to change a common fraction to a decimal and then perform a computation. In the following problems change the common fractions to decimals before performing the computations:
3. An aviator in a trial flight went 1126 miles in 9 hours. Find his average speed per hour.
4. If a customer pays $4.50 for 11 yards of silk, what is the price per yard?
5. Find the cost of 10 tons of hay at $27.50 a ton. 6. A farmer sold a farm containing 92% acres at $187.50
How much did he receive for the farm? 7. Find the number of cubic feet in a bin 124 feet long, 6 feet wide and 5 feet deep. How many bushels will it contain, allowing 14 cubic feet per bushel?
8. How much will 393 pounds of lard cost at 281 cents a pound?
9. How many yards in a rod? Change 440 yards to rods, expressing the divisor in decimal form.
10. There are 43,560 square feet in an acre and 2724 square feet in a square rod. Find the number of square rods in an
11. A bin contains 4183 cubic feet. How many bushels of grain will it hold, allowing 12 cubic feet per bushel?
12. How many pieces of wire 13 feet long can be cut from a piece of wire 57 feet long?