please tell me the OA

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please tell me the OA

by jeegarm » Fri Oct 10, 2008 4:58 am
Q27:
The interior of a rectangular carton is designed by a certain manufacturer to have a
volume of x cubic feet and a ratio of length to width to height of 3 : 2 : 2. In terms of x,
which of the following equals the height of the carton, in feet?
x^1/3
2x/3^1/3 (cuberoot of 2x/3)
3x/2^1/3
2/3x^1/3
3/2x^1/3
Answer:
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by kris610 » Fri Oct 10, 2008 6:36 am
Question has already been posted. Anyway since is it urgent:

You have the ratio of the carton -- 3:2:2 i.e. if the length is 3a, the width and height each would be 2a. So, the volume will be 3a*2a*2a = 12a^3.

Given 12a^3 = x, from which you get a = (cube root of x/12).

You need the height, which is 2a. You get 2*(cube root of x/12). Take 2 inside and simplify-- you will get B.

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by vivek.kapoor83 » Sat Oct 11, 2008 12:13 am
agree B