Find all School-related info fast with the new School-Specific MBA Forum

It is currently 22 Aug 2014, 05:53

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

3 of the hardest questions in GmatPrep!

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Intern
Intern
avatar
Joined: 21 Jan 2007
Posts: 24
Followers: 0

Kudos [?]: 1 [0], given: 0

3 of the hardest questions in GmatPrep! [#permalink] New post 06 Mar 2007, 04:01
Could u help me out with these 3 questions?? The OA is the one circled in blue (while the other is the one i picked =( )

These should be from the hardest ones found on GmatPrep, as i scored 50 in Quant section...

Please provide extensive explanation to the solution, cause i really don't know how to get it!!

Thanks

Riccardo
Attachments

3.jpg
3.jpg [ 137.46 KiB | Viewed 830 times ]

2.jpg
2.jpg [ 88.17 KiB | Viewed 831 times ]

1.jpg
1.jpg [ 127 KiB | Viewed 829 times ]

Kaplan GMAT Prep Discount CodesKnewton GMAT Discount CodesManhattan GMAT Discount Codes
Senior Manager
Senior Manager
avatar
Joined: 23 Jun 2006
Posts: 389
Followers: 1

Kudos [?]: 301 [0], given: 0

GMAT Tests User
 [#permalink] New post 06 Mar 2007, 07:03
first.... well done for scoring 50....

now for the questions:
question 1:
there are 4 possible "session attendance" outcomes:
A: no session
B: morning only
C: afternoon only
D: morning and afternoon

each person of the 128 is exactly in one group.
stem tells us that group A is empty. great.
it also asks how many people are in group B....

st1 tells us that group D has 3/4 of the people.... which means the rest are divided between B and C... so is insufficient.
st2 tells us that "7/8 of the people attended the afternoon session"... what does it mean? which groups from A,B,C,D attended the afternoon session? oh... that's C and D. so C and D together holds 7/8 of the people. where can be the remaining 1/8? true... in group B, which is exactly what we wanted to know. so st2 is sufficient.

answer is B.


question number 2:
to understand your mistake just plug-in x=2 and x=-2 and see that the answer is not always 1. this same example will show you that the result is neither -1,0 nor x. so by elimination you can safely deduce that the answer is E.

question number 3:
lets denote angle QRS by a, RSQ by b, STU by c and TSU by d.
we know that a+d=90 (because it is right triangle).
we also know that c+b+x=180 or x=180-(b+c)
so we miss lots of info.
st1 and st2 are clearly insufficient alone (each one deals with one side and provide no info on the other side of the problem).
lets check them together..
from st1 we know that QRS is isosceles, which means b=(180-a)/2
from st2 we similarly infer that c=(180-d)/2
b+c = (360-a-d)/2 = 270/2 = 135 (because a+d = 90)
so x=45
hence st1,st2 together are sufficient.
Manager
Manager
avatar
Joined: 09 Jan 2007
Posts: 242
Followers: 1

Kudos [?]: 5 [0], given: 0

GMAT Tests User
 [#permalink] New post 06 Mar 2007, 07:40
Explaination 1)

Each person must be a part of either morning or afternoon or both sessions.

7/8 of the group attended afternoon, so remaining 1/8th must be part of morning.

Because remaining 1/8 th of the group either attended morning or did not attend morning (this is not true as it is already mentioned in the statement).
  [#permalink] 06 Mar 2007, 07:40
    Similar topics Author Replies Last post
Similar
Topics:
Experts publish their posts in the topic Hardest questions Bunuel 5 04 Jul 2013, 07:12
Hardest Questions sher676 1 12 Aug 2009, 14:16
Counting challenge question #3 (hardest) brenthanneson 7 06 Dec 2008, 18:32
3 hard bin GmatPrep questions!! eribold 5 01 Mar 2007, 09:05
3 tricky questions from GmatPrep! eribold 5 28 Feb 2007, 03:49
Display posts from previous: Sort by

3 of the hardest questions in GmatPrep!

  Question banks Downloads My Bookmarks Reviews Important topics  


cron

GMAT Club MBA Forum Home| About| Privacy Policy| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group and phpBB SEO

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.