What is the volume of rectangular box Q? (1) Two adjacent

Question

What is the volume of rectangular box Q?

(1) Two adjacent faces of the box Q have areas 10 and 12.

(2) Two opposite faces of box Q each have an area of 30.

sudhir18n · Answer

Volume = l*b*h

st 1: 2 adjacent face has area of 10, 12

so the face can be 10,12,1 or 2, 5,6 ..each case the answer is different 
hence in sufficicent

st 2: opposite faces have an area of 30... clearly insufficient

1 and 2 together

l^2b^2c^2 = 10*12*30
lbh = sqrt(10*12*30)
= 60
hence sufficient

kamalkicks · Answer

=> consider a rectangle box with sides  x,y,z 
 rephrase the question-- what is xyz ?

statement 1 :
 suppose  xy=10,xz=12  can we find out  xyz ?  no
 combining  xy  and  xz  ===  xy^2z=120 
  so 1 insuff

statement 2:
 suppose  xy/yz/xz=30 
 still cannot find xyz
  2 insuff

combine 1 & 2  
  xy=10,xz=12 & yz=30 
 so  (xyz)^2=3600  =:>  xyz=60

so answer is C

i hope it helps

Bunuel · Answer

"Stolen" OG question: Discussed here: https://gmatclub.com/forum/what-is-the-v ... 90748.html Hope it helps.

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