2182 ARITHMETIC
VOLUME.
1728 cubic inches (cu. in.) =1 cubic foot (cu. ft.)
27 cubic feet = l cubic yard (cu. yd.) 128 cubic feet=l cord (cd.) 16 cubic feet=l cord foot (cd. ft.)
8 cord feet=l cord (cd.) A cord of wood is a pile of wood 8 ft. long, 4 ft. wide, and 4 ft. high.
A CORD OF WOOD * CORD FOOT
8 FEET LONG
A rectangular solid is a solid bounded by six rectangles. The rectangles are called the faces of the solid.
A cube is a rectangular solid bounded by six equal faces (squares). The volume of a solid is its contents reckoned in cubic units.
How many cubic feet are there in a rectangular solid 4 ft. long, 2 ft. wide and 4 ft. high?
Multiply the number of cu. ft. in 1 row by the number of rows, to find the number of cubic feet in 1 layer.
Multiply the number of cu. ft. in 1 layer by the number of layers. This gives the number of cu. ft. in the solid.
4 cu. ft. in 1 row. 2
8 cu. ft.
4 (number of layers).
8 cu. ft. in the 2 rows (the bot- —
torn layer). 32 cu. ft. in the solid.
Eule for volume.
To find the volume of a rectangular solid, multiply the area of the base by the height.
