Is sqrt(n+k) > 2*sqrt(n)?

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Source: — Data Sufficiency |

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by Patrick_GMATFix » Sun Mar 09, 2014 6:47 pm
This question tests your understanding that so long as you're dealing with positive values, x>y means that x^2 > y^2. So we can square each side and rephrase the question as: is n+k > 4n? --> is n>3k?

The answer is A. I go through the question in detail in the full solution below (taken from the GMATFix App).

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by theCodeToGMAT » Sun Mar 09, 2014 7:16 pm
n & k = +ve
sqrt(n+k) > 2*sqrt(n)
Or,
n + k > 4n
TO FIND: k > 3n

Statement 1:
k > 3n
SUFFICIENT

Statement 2:
n + k > 3n
k > 2n
INSUFFICIENT

[spoiler]{A}[/spoiler]
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