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

It is currently 21 Sep 2014, 22:26

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

Ben needs to form a committee of 3 from a group of 8

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Manager
Manager
User avatar
Joined: 15 Jul 2004
Posts: 73
Followers: 3

Kudos [?]: 4 [0], given: 0

Ben needs to form a committee of 3 from a group of 8 [#permalink] New post 06 Apr 2005, 10:04
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

50% (02:30) correct 50% (01:12) wrong based on 2 sessions
Ben needs to form a committee of 3 from a group of 8 engineers
to study design improvements for a product. If two of the
engineers are too inexperienced to serve together on the
committee, how many different committees can Ben form?

20
30
50
56
336
_________________

===========================
Let us make hay while the sun shines.
Don Quixote. Part i. Book. iii. Chap. xi.

Senior Manager
Senior Manager
avatar
Joined: 19 Feb 2005
Posts: 492
Location: Milan Italy
Followers: 1

Kudos [?]: 9 [0], given: 0

GMAT Tests User
 [#permalink] New post 06 Apr 2005, 13:30
I'm getting through this by educated guessing...
First: total possible outcomes=8c3=56
so D=56; and E=336 are OUT.
find in how many committees the 2 are together
1*1*6c1=6
so 56-6=50
I learnt the technique of total possible outcomes- unfavorable outcomes in this forum and I'm really grateful to GmatClub
:thanks
However, Hope it's right!
Director
Director
avatar
Joined: 18 Feb 2005
Posts: 674
Followers: 1

Kudos [?]: 2 [0], given: 0

GMAT Tests User
 [#permalink] New post 06 Apr 2005, 15:06
30 ways

The 1 exp guy can be selected in 2C1=2 ways
the rest of the 2 guys can be selected in 6C2 ways
2*6C2 = 30 ways
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 07 Jul 2004
Posts: 5097
Location: Singapore
Followers: 19

Kudos [?]: 144 [0], given: 0

GMAT Tests User
 [#permalink] New post 06 Apr 2005, 18:44
Total number of 3 man team = 8!/3!5! = 56
Total number of teams with 2 inexperienced engineers in the same team = 6!/1!5! = 6
So total number of teams with no 2 inexperienced engineers = 56-6=50

C is the answer
Manager
Manager
User avatar
Joined: 15 Jul 2004
Posts: 73
Followers: 3

Kudos [?]: 4 [0], given: 0

 [#permalink] New post 06 Apr 2005, 20:34
OA is C
:)
_________________

===========================
Let us make hay while the sun shines.
Don Quixote. Part i. Book. iii. Chap. xi.

Manager
Manager
User avatar
Joined: 15 Jul 2004
Posts: 73
Followers: 3

Kudos [?]: 4 [0], given: 0

 [#permalink] New post 06 Apr 2005, 20:44
Could someone write the universal formula for this:

Ben needs to form a committee of X from a group of Y engineers. If Z of the
engineers are too inexperienced to serve together on the
committee, how many different committees can Ben form?

1) Z<X<Y
2) Z<=X<=Y
_________________

===========================
Let us make hay while the sun shines.
Don Quixote. Part i. Book. iii. Chap. xi.

Manager
Manager
avatar
Joined: 28 Oct 2004
Posts: 95
Location: Irvine, CA
Followers: 1

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

 [#permalink] New post 06 Apr 2005, 21:55
just try to think 2 things:

1) total possible outcomes

2) what exception are there, if it is easier to count the exceptions, then we just substract the exceptions from the total outcomes.

this is specially usefull when we are working with outcomes,

when it is about percentages, it is different.

just adding my 3 ctns....
_________________

discipline is what I need.

VP
VP
avatar
Joined: 30 Sep 2004
Posts: 1493
Location: Germany
Followers: 4

Kudos [?]: 49 [0], given: 0

GMAT Tests User
 [#permalink] New post 07 Apr 2005, 01:44
gmat2me2 wrote:
30 ways

The 1 exp guy can be selected in 2C1=2 ways
the rest of the 2 guys can be selected in 6C2 ways
2*6C2 = 30 ways


but your reasoning is also correct. you just forgot to add the combinations without the two engineers:

2*6c2 + 6c3 = 50 :)
_________________

If your mind can conceive it and your heart can believe it, have faith that you can achieve it.

  [#permalink] 07 Apr 2005, 01:44
    Similar topics Author Replies Last post
Similar
Topics:
11 Experts publish their posts in the topic A committee of 2 people is to be formed from a group of 8 MichelleSavina 6 22 Jan 2011, 02:06
8 Experts publish their posts in the topic Ben needs to form a committee of 3 from a group of 8 enginee eltonli 5 15 Jan 2011, 16:28
A committee of 3 has to be formed randomly from a group of 6 MooseDrool 6 23 Aug 2007, 18:48
Ben needs to form a committee of 3 from a group of 8 rc1979 8 23 Apr 2005, 15:10
5 Experts publish their posts in the topic A committee of 3 men and 3 women must be formed from a group Paul 17 02 Feb 2005, 19:11
Display posts from previous: Sort by

Ben needs to form a committee of 3 from a group of 8

  Question banks Downloads My Bookmarks Reviews Important topics  


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®.