GMAT PREP NEGATIVE CUBE ROOT PROBLEM

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GMAT PREP NEGATIVE CUBE ROOT PROBLEM

by rbansal » Tue May 10, 2011 9:57 am
Hello I have the question attached, can someone please help me answer this?
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by Stuart@KaplanGMAT » Tue May 10, 2011 10:00 am
rbansal wrote:Hello I have the question attached, can someone please help me answer this?
Hi,

almost certainly the easiest way to solve this problem is via brute force.

-1^3 = -3
-2^3 = -8
-3^3 = -27
-4^3 = -64
-5^3 = -125

So, the cube root of -89 is between -4 and -5.
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by manpsingh87 » Tue May 10, 2011 10:01 am
rbansal wrote:Hello I have the question attached, can someone please help me answer this?
(-4)^3=-64;
(-5)^3=-125;
given cube root of (-81); which will definitely lie between -4 and -5; here easiest way to solve is to work with the options..!!!
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