SOLUTION: When 0.5 cm was planed off each of the six faces of a wooden cube, its volume decreased by 169 cm^3. Find its new volume.
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Question 239703: When 0.5 cm was planed off each of the six faces of a wooden cube, its volume decreased by 169 cm^3. Find its new volume. Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! When 0.5 cm was planed off each of the six faces of a wooden cube, its volume decreased by 169 cm^3. Find its new volume.
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Each side is decreased by 1 cm, 0.5 on each face.
(s+1)^3 = s^3 + 169
s^3 + 3s^2 + 3s + 1 = s^3 + 169
3s^2 + 3s - 168 = 0
s^2 + s - 56 = 0
(s + 8)*(s - 7) = 0
s = 7 cm
V = 7^3
V = 343 cc
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343 + 169 = 512 = 8^3
