geometry

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geometry

by Gurpinder » Fri Sep 17, 2010 10:48 am
Image
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by kvcpk » Fri Sep 17, 2010 2:38 pm
When the bar is melted and re-formed, the volume of the bar will remain same.
Hence 12*18*15 should remain same.
12*18*15 = 3^4*2^3*5

To put it algebraically, the question is now asking, which option has different factors from above.

A has a factor of 11. Hence A should be the answer.

Hope this helps!!
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by sanju09 » Fri Sep 17, 2010 10:34 pm
Gurpinder wrote:Image

While melting and recast, what remains unchanged is the volume, if not stated if not.

Hence, the new dimensions must also multiply up to bring 12 × 18 × 15, or it should have only 2, 3, and 5 as its prime factors. Choice [spoiler]A[/spoiler] includes 22, and 11 is not among the tolerable 2, 3, and 5.

[spoiler]A[/spoiler]
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