A solid box is 25 cm by 20 cm by 8 cm. A new solid is formed by removing a cube 5 cm on a side from each corner of this box. What percent of the original volume is removed?

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Answer 1 · 2018-06-18T06:59:05

#12 1/2%#

The original volume is #20xx25xx8=4000 cm^3#

a 5 cm cube has a volume of #5xx5xx5=125 cm^3#

On a cuboid there are 8 vertices so that you would have a cube removed at each one

#8xx125=1000#

#1000/4000=1/4 or 25%#

But I have just realized if you remove a cube from the top and the bottom you are removing 10 cm in height but the box is only 8 cm high!

So just remove 4 of the cubes

#4xx125=500#

#500/4000=1/8=12 1/2%#