What is the volume of a regular-shaped object if you measure its length, width, and height and multiply?

• A. Multiply length by width by height.
• B. Add length, width, and height.
• C. Divide mass by volume.
• D. Multiply mass by density.

Answer: (A)

Volume tells you how much space is inside a object. For a regular-shaped one like a box, you find that space by using its three dimensions—length, width, and height—and multiplying them together. This works because you’re filling the object in all three directions, so you multiply each measurement to get the total space inside. The units come out cubic, like cubic centimeters, when you multiply units of length.

If you added the dimensions, you’d be mixing measurements in a way that doesn’t describe inside space. The other ideas involve mass and how much matter is packed, not space: density is mass per unit volume, so you’d divide mass by volume to get density, and multiplying mass by density doesn’t give volume. So multiplying length, width, and height is the way to get the volume.