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Last Updated on May 10, 2023
GMAT OFFICIAL GUIDE DS
Solution:
We are given that n and k are positive integers, and we must determine whether √(n + k)> 2√n.
We first square both sides of the given inequality. Doing so gives us:
Is n + k > 4n ?
Is k > 3n ?
Statement One Alone:
k > 3n
Statement one answers the question directly that k is greater than 3n. We can eliminate answer choices B, C, and E.
Statement Two Alone:
n + k > 3n
We can simplify the inequality in statement two.
n + k > 3n
k > 2n
Recall that the simplified question asks whether k is greater than 3n. Since we only know that k is greater than 2n using statement two, we see that statement two is not sufficient to answer the question.
Answer: A
