An object weighs 150 lbs per cubic foot and measures 4 ft X 3 ft X 3 ft, what is its weight?

An object weighs 150 lbs per cubic foot and measures 4 ft X 3 ft X 3 ft, what is its weight?

• A. 540 lbs
• B. 450 lbs
• C. 4,500 lbs
• D. 5,400 lbs

Answer: (D)

To find the weight, multiply the volume by the weight per cubic foot. The object is a rectangular block with dimensions 4 ft by 3 ft by 3 ft, so its volume is 4 × 3 × 3 = 36 cubic feet. With a density of 150 pounds per cubic foot, the weight is 36 × 150 = 5,400 pounds. So the object weighs 5,400 pounds. The other numbers wouldn’t fit the actual volume: they correspond to smaller volumes (for example, 3.6 or 3 cubic feet) or a larger one (30 cubic feet), but the computed volume is 36 cubic feet.

To find the weight, multiply the volume by the weight per cubic foot. The object is a rectangular block with dimensions 4 ft by 3 ft by 3 ft, so its volume is 4 × 3 × 3 = 36 cubic feet. With a density of 150 pounds per cubic foot, the weight is 36 × 150 = 5,400 pounds. So the object weighs 5,400 pounds. The other numbers wouldn’t fit the actual volume: they correspond to smaller volumes (for example, 3.6 or 3 cubic feet) or a larger one (30 cubic feet), but the computed volume is 36 cubic feet.