500 ds test4 #18

dunkin77 · Posted: Thu Apr 05, 2007 5:43 pm Post subject: 500 ds test4 #18

Hi,

I thought the answer is E) or C) but turned out to be D)....

I thought even thought the total area is same, the length of each side could be different, and thus the volum could be different.... If the answer is D), that means the cube that has the same area size always have the same volum size too?

. What is the volume of a certain cube?
(1) The sum of the areas of the faces of the cube is 54.
(2) The greatest possible distance between two points on the cube is

jayhawk2001 · Posted: Thu Apr 05, 2007 10:19 pm Post subject:

A cube has sides of the same length.

1 - sufficient. 6a^2 = 54. we can hence calculate a^3

2 - sufficient. You don't need to solve this. It is enough to know that
the greatest distance between 2 points can be represented in
terms of side a.

Hence D

dunkin77 · Posted: Thu Apr 05, 2007 10:50 pm Post subject:

Thank you - if cube always has the same length... that will explain !! Razz