cube root

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by sanju09 » Sat Apr 24, 2010 12:59 am
cat er ina wrote:Which of the following is the closest to ∛ 2.539 (cube root of 2.539) ?
Can someone help me with this one please?
You luckily have 2539/1000 to determine the cube root of. Rough estimation takes it somewhere around 2500/1000 = 20/8. Now, cube root of 8 is 2, and that of 20 is pretty less than 3, it'll be nearly 2.7 or something. So the cube root of 2.539 will be very close to [spoiler]1.35[/spoiler], as per my figment of imagination. Where are the options that were following in the stem?

I assure you that the GMAT would never put you in such trouble ever. Moreover, if a math question is not in the ideal PS form of GMAT, then please post the same in the GMAT MATH forum of beatthegmat.

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by pradeepkaushal9518 » Sat Apr 24, 2010 1:02 am
what are the options?

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by cat er ina » Sat Apr 24, 2010 1:16 am
sanju09 wrote:
cat er ina wrote:Which of the following is the closest to ∛ 2.539 (cube root of 2.539) ?
Can someone help me with this one please?
You luckily have 2539/1000 to determine the cube root of. Rough estimation takes it somewhere around 2500/1000 = 20/8. Now, cube root of 8 is 2, and that of 20 is pretty less than 3, it'll be nearly 2.7 or something. So the cube root of 2.539 will be very close to [spoiler]1.35[/spoiler], as per my figment of imagination. Where are the options that were following in the stem?

I assure you that the GMAT would never put you in such trouble ever. Moreover, if a math question is not in the ideal PS form of GMAT, then please post the same in the GMAT MATH forum of beatthegmat.

Best wishes
well I guess we could say that when you think this gmat test can t get worst it really does because I found this during my test about two months ago and just looked at it for 2 minutes clueless..lol..

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by cat er ina » Sat Apr 24, 2010 1:18 am
cat er ina wrote:
sanju09 wrote:
cat er ina wrote:Which of the following is the closest to ∛ 2.539 (cube root of 2.539) ?
Can someone help me with this one please?
You luckily have 2539/1000 to determine the cube root of. Rough estimation takes it somewhere around 2500/1000 = 20/8. Now, cube root of 8 is 2, and that of 20 is pretty less than 3, it'll be nearly 2.7 or something. So the cube root of 2.539 will be very close to [spoiler]1.35[/spoiler], as per my figment of imagination. Where are the options that were following in the stem?

I assure you that the GMAT would never put you in such trouble ever. Moreover, if a math question is not in the ideal PS form of GMAT, then please post the same in the GMAT MATH forum of beatthegmat.

Best wishes
well I guess we could say that when you think this gmat test can t get worse it really does because I found this during my test about two months ago and just looked at it for 2 minutes clueless..lol..

can t remember options sorry

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by frank1 » Sat Apr 24, 2010 1:41 am
i think for this question i would try solving backwords
i know cuberoot of 2 is around 1.25
so i will try to search option in that range...

if they give you 1.28 and 1.31 and so on ...very lucky....
After all i think 700 is also much about luck

The method mentioned in above post doesnt work for all numbers i guess

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by Fiver » Sat Apr 24, 2010 7:42 am
cat er ina wrote:Which of the following is the closest to ∛ 2.539 (cube root of 2.539) ?
Can someone help me with this one please?
If this question were to read as 'Which of the following is the closest to 2.236 * (cube root of 2.236) ?'
it would have been quite an interesting GMAT like question.