If cubical blocks in a display are stacked one on top of the other on

Question

If cubical blocks in a display are stacked one on top of the other on a flat surface, what is the volume of the stack of blocks in cubic centimeters?

(1) The volume of the top block is 8 cubic centimeters.
(2) The height of the stack of blocks is 10 centimeters.#

DS12402.01

dcummins · Accepted Answer

Official Solution 
 
DS12402.01

It is given that the volume of the top cube in the stack is 8 cubic centimeters, from which it follows that the top block has edges of length 2 cm, but no information is given about the size of the other blocks in the stack or how many blocks the stack contains; NOT sufficient.

It is given that the height of the stack of blocks is 10 cm, but no information is given about the size of any of the blocks in the stack or how many blocks are in the stack.
Taking (1) and (2) together gives no information about the size of the blocks below the top block or how many blocks are in the stack. For example, there could be two blocks with edges of lengths 2 cm and 8 cm. The volume of the top block would be 8 cubic centimeters, the height of the stack would be 10 cm, and the volume of the stack of blocks would be 520 cubic centimeters. But there could also be three blocks with edges of lengths 2 cm, 3 cm, and 5 cm. The volume of the top block would be 8 cubic centimeters, the height of the stack would be 10 cm, and the volume of the stack of blocks would be 160 cubic centimeters.

Both statements together are still not sufficient.

Tip: Do not assume anything that is not explicitly stated in the problem. In this problem, it is tempting to assume that all of the blocks are identical, in which case there would be five blocks, each with height 2 cm to give the whole stack a height of 10 cm and a volume of 40 cubic centimeters. Under the assumption that all of the blocks are identical, the correct answer would be C.

itoyj · Answer

Can anyone help-
I have a doubt, since it is not mentioned is the stacked cuboid are of same dimensions, can we assume it?
Or we need to go with the all the corner cases, that they might not be of same size?

Posted from my mobile device

DavidTutorexamPAL · Answer

If it is not mentioned, we cannot assume it.

askme13 · Answer

Isnt the definition of a cube all same sides?

that is what was written for this problem what-is-the-volume-of-a-certain-cube-176165

VeritasKarishma

Bunnell - any tips here?

happiness10 · Answer

if we combine both statements the only case comes out to be 2 as side
then ans must be c
why it is E??

Basshead · Answer

If cubical blocks in a display are stacked one on top of the other on a flat surface, what is the volume of the stack of blocks in cubic centimeters?

The key takeaway for this question is that we can't assume all the cubical blocks are the same size. If it's not mentioned in the question, we can't assume it.

(1) The volume of the top block is 8 cubic centimeters.

No information on the other blocks. INSUFFICIENT.

(2) The height of the stack of blocks is 10 centimeters.

We can't determine the volume of each box. INSUFFICIENT.

(1&2) Combined, we still can't determine the volume of the stack of boxes. INSUFFICIENT.

Answer is E.

faat99 · Answer

This is the crux of this question, in fact there is no maths involved in this Q, but more the "reasoning", same rule for all GAMT question, you can't make assumption base on your knowledge outside what is stated in the question

Poojita · Answer

Can we assume here that we have only one stack of blocks?

Anki111 · Answer

DS12402.01

Can we assume here that we have only one stack of blocks?

No, we can not assume anything. We don't know how many stacks are there on the top part. We know the top one block but that doesn't suffice that all others are identical. So, both the statements are not sufficient.

If cubical blocks in a display are stacked one on top of the other on

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