A monument is made from rectangular blocks of marble measure

Question

A monument is made from rectangular blocks of marble measure 2 feet by 3 feet by 1 foot. These blocks are stacked to form a rectangualr solid of marble. If all the blocks in the same direction, how many blocks high is the monument?

1) The lenght of the monument is 12 feet and the width of the monument is 15 feet

2) the height of the monument is 25 feet.

Pls explain....

rthothad · Answer

Is it A. 
Will explain if correct

july05 · Answer

B? 

in A there are 3 possible ways to arrange the blocks. 

it looks like it's one way in B

sparky · Answer

B.

1) insuff we don;t know how many blocks are stacked
2) suff 25 can only be divided by 1 so => the monument is 25 feet high or 25 blocks high

gmat2me2 · Answer

sparky is right....it has to be B since the blocks are all in one direction

Antmavel · Answer

I used the same method as sparky to find that the second statement is suff. 25 is not a multiple of 2 and it is not a multiple of 3 so the height is 1 for sure However I found strange that the statement 1 seems totally wrong. Can someone explain the 1st statement in detail because I can not find the way to get 12 in lenght and 15 is width

if lenght is 1 -> 12 -> 12 blocks so width should be 12*2 = 24 or 12*3 = 36 if lenght is 2 -> 12 -> 6 blocks so width should be 6*1 = 6 or 6*3 = 18 if lenght is 3 -> 12 -> 4 blocks so width should be 4*1 = 4 or 4*3 = 12 However it is 15... I am not saying that B is not the answer but it is very rare that they put a totally wrong statement, usually the statements is verified by many potential answers whereas this one is totally impossible...

Maybe I am wrong, so please...

ssap · Answer

B for me too.
According to Stmt 1: 
lenghth = 12 
so u can use either the side of measuremet 2 or 3
But using 3 will not work - If you use multiples of 3 for a lenght of 12, then u cannot use side of measurement 2 to fulfill the width. 'coz the reqd width 15 is NOt a multiple of 2. 
HEnce only one configuration is possible :
Use 6 blocks with side(2) to make up the lenght 
and 5 blocks with side (3) to make up the width
Hope it's clear. Wish I cld draw it out!

AJB77 · Answer

Block 2 x 3 x 1 feet

S1 - l = 12, w = 15

This says nothing about the height or the number of blocks high. We can arrive at the above by either using the 2 feet side or 3 feet side for length . But in any case, once we get a particular top-view to match 12 x 15, we can keep stacking it to get many different heights ad infinitum.

So insufficient. Scratch A and D

S2 - Height of the monument is 25 feet. 25 is not divisible by 2 or 3, so the only way this can be formed is by stacking 25 blocks wit the 1 ft side being the height. => Sufficient.

B is my answer

Darth_McDaddy · Answer

The answer should be B

The question asks how many bricks high is the monument. Only B, gives you the height of the monument. Therefore the answer is 25 feet / 1 feet = 25 Bricks

A is insuff, as it doesn't mention the height of the monument.

Arsene_Wenger · Answer

Agree with Darth. It's (B) for me too.

A monument is made from rectangular blocks of marble measure

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