Bunuel wrote:
What is the cube root of w?
(1) The 5th root of w is 64.
(2) The 15th root of w is 4.
Target question: What is the cube root of w? Statement 1: The 5th root of w is 64. ASIDE: If the square root of x = 7, then x = 7²
If the cube root of x = 10, then x = 10³
If the fourth root of x = 6, then x = 6⁴
etcSo, if the 5th root of w is 64, then w = 64⁵
Since we COULD determine the actual value of w, we COULD find
the cube root of wIn other words, we have all of the information we need to answer the
target question with certainty
Statement 1 is SUFFICIENT
Statement 2: The 15th root of w is 4From this we can conclude that w = 4¹⁵
Since we COULD determine the actual value of w, we COULD find
the cube root of wIn other words, we have all of the information we need to answer the
target question with certainty
Statement 2 is SUFFICIENT
Answer: D
Cheers,
Brent
_________________
Brent Hanneson – Creator of gmatprepnow.com
I’ve spent the last 20 years helping students overcome their difficulties with GMAT math, and the biggest thing I’ve learned is…
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