GMAT PAPER TEST PS

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GMAT PAPER TEST PS

by smclean23 » Mon Dec 29, 2008 6:50 pm
*Imagine a tank that is 1200 cm long, 960 wide, and 120cm tall (had trouble cropping from PDF*

How many cubic centimeters of water are in the tank when the water level is 10 cm below the top of the tank?


12,672,000

13,824,000

126,720,000

138,240,000

1,267,200,000

OA is C....Sorry but you guys are smart so you will be able to use your imagination.
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by Sachindh » Mon Dec 29, 2008 7:05 pm
The height of the water level in tank 10 cm below the top shall be equal to 110.

Therefore volume of water in tank shall be = 1200 * 960 * 110 cu cm
=> 126,720,000

Hence C

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by Stuart@KaplanGMAT » Mon Dec 29, 2008 10:00 pm
Sachindh wrote:The height of the water level in tank 10 cm below the top shall be equal to 110.

Therefore volume of water in tank shall be = 1200 * 960 * 110 cu cm
=> 126,720,000

Hence C
100% correct. However, we can save ourselves some calculation time.

Looking at the choices, they're pretty well spread out, which means that it's safe to round off. If you ever find yourself doing massive calculations on test day, you've missed a shortcut. GMAC fully recognizes that everyone has a calculator, computer or accounting department to do those messy calculations and isn't testing us on our ability to do long multiplication or division problems.

So, instead of 1200 * 960 * 110 , let's use 1200*1000*100 = 120,000,000... choose (C).
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