Data Sufficiency

Hi All,

Following is Q#18 of OG-12.

[spoiler]OA = B. For giving the result to be B...OG in its explanation considers all the three possible scenarios...i.e. when box rests on
a) 60 by 30,
b) 60 by 20
and c) 30 by 20

In all the three cases, the number of small boxes comes to be same = 125. Can someone please tell why do we need to consider all the three cases, since we need to know the maximum number of small boxes....so once we know the dimensions of smaller and larger box then we can for sure calculate the maximum...isn't it ?

Please tell what I am missing here ?[/spoiler]

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What is the maximum number of rectangular blocks, each with dimensions 12 centimeters by 6 centimetres by 4 centimetres, that will fit inside rectangular Box X ?

1) When box X is filled with the blocks and rests on a certain side, there are 25 blocks in the bottom layer.
2) The inside dimensions of box X are 60 centimetres by 30 centimetres by 20 centimetres.

I dont think u need to consider all three cases... Only thing which we need to know is that whether we are able to calculate the number of boxes or not and that can be done by B.