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2003 AMC 10A Problems/Problem 3

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Problem

A solid box is 15 cm by 10 cm by 8 cm. A new solid is formed by removing a cube 3 cm on a side from each corner of this box. What percent of the original volume is removed?

\mathrm{(A) \ } 4.5\qquad \mathrm{(B) \ } 9\qquad \mathrm{(C) \ } 12\qquad \mathrm{(D) \ } 18\qquad \mathrm{(E) \ } 24

Solution

The volume of the original box is 15cm\cdot10cm\cdot8cm=1200cm^{3}

The volume of each cube that is removed is 3cm\cdot3cm\cdot3cm=27cm^{3}

Since there are 8 corners on the box, 8 cubes are removed.

So the total volume removed is 8\cdot27cm^{3}=216cm^{3}.

Therefore, the desired percentage is \frac{216}{1200}\cdot100 = 18\% \rightarrow D.

See also

2003 AMC 10A (ProblemsResources)
Preceded by
Problem 2
Followed by
Problem 4
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
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