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Official Guide 13th Edition - Question #15

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by alex.gellatly » Tue Aug 28, 2012 5:59 pm
patheinemann wrote:hi guys,

would someone help me with the strategy and approach to the DS question #15 on the new OG

"What is the cube root of w?"

(1) The 5th root of w is 64
(2) The 15th root of w is 4
The correct answer is D and here's why:

In the question stem it is asking for the cube root of w. which is equal to w^(1/3)

1) The 5th root of w is 64 this means w=64^5; we can now calculate the cube root of w. [(64^5)^1/3] This is sufficient. Remember in DS questions we don't actually have to find the answer.

2) This is sufficient for the same reason that 1 is; w=4^15 so [(4^15)^1/3]

Let me know if this helps
A useful website I found that has every quant OG video explanation:

https://www.beatthegmat.com/useful-websi ... tml#475231
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by Anurag@Gurome » Tue Aug 28, 2012 10:52 pm
patheinemann wrote:hi guys,

would someone help me with the strategy and approach to the DS question #15 on the new OG

"What is the cube root of w?"

(1) The 5th root of w is 64
(2) The 15th root of w is 4

The correct answer is (D), however I frankly don't understand the approach.
You can see my reply here: https://www.beatthegmat.com/og13-ds-q15- ... 14709.html
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by patheinemann » Wed Aug 29, 2012 7:29 am
Excellent. My approach problem had to do on leaving w alone as a variable.

Thanks and by the way alex.gellatly do you know if videos for OG 13 are available. Haven´t found them yet.
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