1. This school garden is 109 ft. wide and 200 ft. long. Find its perimeter. 2. How many plants would be used to plant a hedge around this garden if a plant is placed every 3 feet? 3. The part of the garden planted with flowers contained 4 violet beds each 4 ft. by 12 ft. How many square feet were planted in violets? 4. The number of blossoms cut each day from the plot planted in sweet peas averaged 24 during the months of July and August. How many dozen blossoms were cut during the two months? 5. How many plants will be needed for an aster bed of 16 rows with 28 plants in a row? 6. The children worked 40 minutes in this garden on 3 days of each week. How many hours did they spend in this work in 4 school weeks? Length Surface 80. Measuring Volume-Cubic Measure You have learned how to measure lengths and surfaces. You are now ready to measure volume. A cubic inch is 1 inch wide, 1 inch long, and 1 inch thick. A cubic foot is 1 foot long, 1 foot wide, and 1 foot thick. A cubic yard is 1 yard long, 1 yard wide, and 1 yard thick. Volume 1. You can build a 2-inch cube, with cubic-inch blocks. (Perhaps you can get some 1-inch cubes from a carpenter.) Put 2 cubic inches in a row. Put 2 more by them. How many cubic inches are there in this layer? Now put 4 cubic inches on top of this layer. How many cubic inches are there in the two layers? How long is this cube? How wide? How thick? It is 2 in. x 2 in. × 2 in., and it contains 8 cubic inches. The convenient way of finding the volume of anything is to multiply length by width by thickness. 2. Find the number of cubic inches in a cube 3 in. X 3 in. x 3 in.; in a cube 4 in. X 4 in. X 4 in. 3. Tell how many inch cubes of chocolates can be put into boxes which are: 6 inches long, 2 inches wide, 2 inches high. 10 inches long, 3 inches wide, 3 inches high. 4. A cubic foot is a cube 1 foot long, 1 foot wide, and 1 foot high. How many inches are there in the length of a cubic foot? In its width? In its height? 12X12X12=1728. There are 1728 cubic inches in a cubic foot. 5. A cubic yard is a cube 1 yard long, 1 yard wide, and 1 yard high. How many feet are there in the length of a cubic yard? In its width? In its height? 3X3X3=27. There are 27 cu. ft. in a cubic yard. The Table of Cubic Measure 1728 cubic inches (cu. in.) = 1 cubic foot (cu. ft.) 27 cubic feet (cu. ft.) 1 cubic yard (cu. yd.) = 6. Without using your pencil, find the number of cubic feet in blocks that are: 4 ft. long, 3 ft. wide, and 2 ft. high. 7 ft. long, 2 ft. wide, and 2 ft. high. 7. Without using your pencil, find the number of cubic yards in blocks that are: 3 yd. long, 2 yd. wide, and 2 yd. high. 81. Thinking out Problems at the Store William, who worked in a store, told the teacher that he had to do most of the problems "in his head." Here are some of the problems he had to solve. See if you can find the cost of the following articles without using a pencil: 1. A can of peas at 18 cents, a loaf of bread at 9 cents, and a half a pound of butter at 40 cents a pound. 2. 8 oranges at 60¢ a dozen and a box of cakes at 12¢. 3. 6 pounds of sugar at 7 cents a pound and 3 cakes of soap at 7 cents each. 4. 3 lemons at 24 cents a dozen and 6 oranges at 60 cents a dozen. 5. 2 pounds of butter at 40 cents a pound. 6. 6 cakes of soap at 3 for 20 cents and a pound of nuts at 28 cents. 7. 18 oranges at 48 cents a dozen and 6 lemons at 30 cents a dozen. 8. 10 muskmelons at the rate of 2 for 25 cents. 9. 8 ounces of candy at 24 cents a pound. 82. Bills When a person buys several articles at a store, the merchant sometimes makes out a bill showing the quantity of each article purchased and the price. In this way the purchaser is able to tell whether the amount of his bill is correct. |