GMAT Prep problem: multiple square roots

Expert replies

ReyWilli: Junior | Next Rank: 30 Posts; Posts: 21; Joined: Mon Jul 20, 2009 11:57 pm

by ReyWilli » Tue Sep 29, 2009 11:14 am

Hi,

Can someone help me solve this problem? I can't figure out how they arrived at the answer.

(See attachment)

Thanks,
FM

Attachments

GMATJunky

Like this post

Source: Beat The GMAT — Problem Solving | Tue Sep 29, 2009 11:14 am

bfman: Senior | Next Rank: 100 Posts; Posts: 63; Joined: Tue Mar 31, 2009 3:53 pm

by bfman » Tue Sep 29, 2009 11:31 am

Are these nested roots? or separate roots?

Like this post

bfman: Senior | Next Rank: 100 Posts; Posts: 63; Joined: Tue Mar 31, 2009 3:53 pm

by bfman » Tue Sep 29, 2009 11:32 am

Are these nested roots? or separate roots?

Like this post

sanjana: Master | Next Rank: 500 Posts; Posts: 182; Joined: Sun Aug 02, 2009 7:19 pm; Thanked: 18 times; GMAT Score:680

by sanjana » Wed Sep 30, 2009 7:43 pm

Firstly these are nested roots.

I would prefer to go backwards on this one.

If for any answer choice you can get a negative root you would pick that one.

For 5,

SQRT(2-SQRT(5)) will result in a -ve root as sqrt 5 > 2
Therefor you would result in a SQRT(-ve) number(i.e an imaginary number)I would pick 5.

For all the other options,if you simply substitute the values you will get +ve square roots.

Like this post

Post new topic Post Reply

• Page 1 of 1

GMAT Course Reviews

560 reviews

1168 reviews

431 reviews

359 reviews

147 reviews

5/5

5 Star (560 Reviews)

"Target Test Prep is the closest to the official version of the GMAT exam, about 99% accuracy in terms of the quality and quantity of information. The course has excellently created singular sets of focused lessons and tests for every possible topic that one could come across in the official GMAT exam."

"The TTP course maximizes the efficiency of the time you spend studying. It will take time and effort but I could almost guarantee that if you complete the course exactly as it is laid out you will get an amazing score. They also have a very responsive team willing to help with any questions you might have."

"TTP has two things that I think no other test prep company offers: A teaching approach that reinforces understanding and an attitude that will give you the mental preparedness needed to succeed on the test. TTP gives you a deep understanding of the concept you need to know while teaching you how to think."

Write a Review