Find the volume of wood used in making a closed box 20 cm by 12 cm by 9 cm if the wood is 1 cm thick.

answer from book: 900cm^3

L x W x H is the only formula right? how come it is 900 cm^3?

please guide me on this please

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- November 18th 2012, 05:20 AMrcsvolume of box
Find the volume of wood used in making a closed box 20 cm by 12 cm by 9 cm if the wood is 1 cm thick.

answer from book: 900cm^3

L x W x H is the only formula right? how come it is 900 cm^3?

please guide me on this please - November 18th 2012, 05:26 AMHallsofIvyRe: volume of box
That is the formula for the volume of a rectangular

**solid**. A box is not solid! 20x 12 x 9 cubic centimeter is the volume of the box**including**the interior. Since each side is 1 cm thick, the interior is 18 by 10 by 7 cm. - November 18th 2012, 06:15 AMrcsRe: volume of box
- November 18th 2012, 07:15 AMProve ItRe: volume of box
What you want is the volume of the WOOD. To evaluate this, you need to evaluate the volume of the entire amount of space up to the boundaries (i.e. 20 x 12 x 9 = 2160) and subtract the "empty space" (i.e. 18 x 10 x 7 = 1260).