GMAT Prep DS Slab

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GMAT Prep DS Slab

by moneyman » Tue Nov 04, 2008 8:24 am
I have problem visualising problems like this one.

My approach:
Stat 1 gives the value for 0.1 thickness as $160

Stat 2 gives the value for 1 meter lenght as $200

Hence I chose C
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Maxx

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by moneyman » Wed Nov 05, 2008 3:15 am
Moderators pls help me on this question.
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by jimmiejaz » Wed Nov 05, 2008 3:59 am
Hi Maxx,

Is the answer D.

If yes, well this is an interesting question with a little trick.
If you carefully check, its a square cuboid. So, all 3 dimensions are known.
In the first choice...
2*2*.2 costs $160 more than 2*2*.1
in the second choice
3*3*.1 costs $200 more than 2*2*.1

we can get a solution from both.
We have to find how much it costs for 3*3*.1

hope it helps...

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by logitech » Wed Nov 05, 2008 9:28 am
jimmiejaz wrote:Hi Maxx,

Is the answer D.

If yes, well this is an interesting question with a little trick.
If you carefully check, its a square cuboid. So, all 3 dimensions are known.
In the first choice...
2*2*.2 costs $160 more than 2*2*.1
in the second choice
3*3*.1 costs $200 more than 2*2*.1

we can get a solution from both.
We have to find how much it costs for 3*3*.1

hope it helps...
I agree with Maxx.

Both statement gives us enough information to find out what 3x3x1 costs!
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by 4meonly » Thu Nov 06, 2008 9:18 am
Agree with D

to answer the main Q we should found the price of 1 unit (1 meter). Let it be x $.
Main Q is 3*3*0,1*x=?$, or 0,9x=?$

(1)
2*2*0,2*x=2*2*0,1*x+160$
x can be found
SUFF

(2)
3*3*0,1*x=2*2*0,1*x + 200$
x can be found
SUFF


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by moneyman » Sun Nov 16, 2008 9:55 am
Sorry but still not clear guys
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by lachlanc » Sun Nov 16, 2008 2:15 pm
using statement (1), find the cubic dimensions of each slab -

2^2*0.2 = 0.8 cubic meters
2^2*0.1 = 0.4 cubic meters

Find the difference between slabs => 0.8 - 0.4 = 0.4
This 0.4 represents $160
Therefore, the slabs sell at $40 per 0.1 cubic meter (or $400 per cubic meter)

SUFFICIENT

same goes for statement (2)

3^2*0.1 = 0.9
2^2*0.1 = 0.4

Difference here is 0.5 which = $200 => 200/0.5 = $400 per cubic meter

SUFFICIENT

Does that help?

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by pbanavara » Sun Nov 16, 2008 6:31 pm
A rather simple way:

From stmnt 1 : For a length of 2 m and a thickness of 0.1 mm (difference)- cost is 120 - so for a length of 3 and thickness 0.1 - what's the cost ? Sufficient

From stmnt 2 : Applying the same logic for stmnt 2 but instead of thickness take length - sufficient

so D

Hope this helps

- pradeep