Aquarium

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Aquarium

by rockeyb » Tue Apr 06, 2010 4:54 am
A rectangular aquarium provides 36 sq cm of water surface area per fish . How many fish are there in the aquarium .

(1) The edges of the aquarium have lengths of 60 ,42 and 30 centimeters.

(2)The aquarium is filled to a depth of 40 centimeters.
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by lkm » Tue Apr 06, 2010 5:07 am
IMO (E).

To find the surface area, you need two things: Breadth X Length.

Statement 1, tells about the all the three things but does not tells which value is equal to Length or Breadth.

Hence INSUFFICIENT.

Statement 2 tells about Depth only, hence INSUFFICIENT.

Taking both statement as together is also INSUFFICIENT

because if the tank is filled up to 40 cms then depth could be either 42 cms or 60 cms. Hence, you still cannot deduce which one is correct Length.

Choose (E)
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by bigge2win » Sat Jul 28, 2012 7:59 pm
The solution in the Kaplan book says that the water surface area is the exposed portion on the top of the aquarium. I was initially confused when I read the question, because I didn't understand what it meant by water surface area. How do you come to the conclusion that it was referring to the top and that it's opened? It's not necessarily true that an aquarium is open at the top. It could've been interpreted as surface area around the whole aquarium.

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by KapTeacherEli » Mon Jul 30, 2012 8:37 pm
bigge2win wrote:The solution in the Kaplan book says that the water surface area is the exposed portion on the top of the aquarium. I was initially confused when I read the question, because I didn't understand what it meant by water surface area. How do you come to the conclusion that it was referring to the top and that it's opened? It's not necessarily true that an aquarium is open at the top. It could've been interpreted as surface area around the whole aquarium.
If you fill a tank with water, then gravity and the nature of liquids mean the water will touch the bottom and all four walls; the top of the water will lie flat, exposed to air (even if the top of the tank is closed off). This top is, conventionally, the surface area of the water--although it's possible that this is considered too idiomatic for the GMAT, which might be more specific!
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