It is currently 21 Sep 2017, 18:05

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.

Close

Request Expert Reply

Confirm Cancel

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

One of 5 pens is faulty. They are tested one at a time, what

  post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
Senior Manager
Senior Manager
avatar
Joined: 05 Jun 2008
Posts: 304

Kudos [?]: 170 [0], given: 0

One of 5 pens is faulty. They are tested one at a time, what [#permalink]

Show Tags

New post 15 Oct 2008, 05:58
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions

HideShow timer Statistics

This topic is locked. If you want to discuss this question please re-post it in the respective forum.

One of 5 pens is faulty. They are tested one at a time, what is the probability that the faulty pen is :
(a) 1th first one tested (b) the 2nd one testedt
(b) the rd one tested (d) the last one tested

Kudos [?]: 170 [0], given: 0

SVP
SVP
User avatar
Joined: 29 Aug 2007
Posts: 2473

Kudos [?]: 832 [0], given: 19

Re: PSP001 [#permalink]

Show Tags

New post 15 Oct 2008, 14:32
vivektripathi wrote:
One of 5 pens is faulty. They are tested one at a time, what is the probability that the faulty pen is :

(a) 1th first one tested (b) the 2nd one testedt
(b) the 3rd one tested (d) the last one tested


a) 1/5
b) 1/4
c) 1/3
d) 1

Edit: I supposed no/without repleshment.
_________________

Verbal: http://gmatclub.com/forum/new-to-the-verbal-forum-please-read-this-first-77546.html
Math: http://gmatclub.com/forum/new-to-the-math-forum-please-read-this-first-77764.html
Gmat: http://gmatclub.com/forum/everything-you-need-to-prepare-for-the-gmat-revised-77983.html


GT

Kudos [?]: 832 [0], given: 19

Senior Manager
Senior Manager
avatar
Joined: 31 Jul 2008
Posts: 294

Kudos [?]: 54 [0], given: 0

Re: PSP001 [#permalink]

Show Tags

New post 15 Oct 2008, 16:01
well :

i get 1/5 for all of them :shock:

Kudos [?]: 54 [0], given: 0

Manager
Manager
avatar
Joined: 12 Feb 2008
Posts: 177

Kudos [?]: 46 [0], given: 0

Re: PSP001 [#permalink]

Show Tags

New post 16 Oct 2008, 08:18
stallone wrote:
well :

i get 1/5 for all of them :shock:


every time you pick one, the # of total decreases, since no replacement.
so when you pick the second one to be defective there is 1 defective out of 4 total.
when you pick the 3rd to be defective, you have already picked two good one before, so the total should be 3, and 1 of these 3 is defective.
i hope this helps. :lol:

Kudos [?]: 46 [0], given: 0

Senior Manager
Senior Manager
avatar
Joined: 05 Jun 2008
Posts: 304

Kudos [?]: 170 [0], given: 0

Re: PSP001 [#permalink]

Show Tags

New post 17 Oct 2008, 01:25
vivektripathi wrote:
One of 5 pens is faulty. They are tested one at a time, what is the probability that the faulty pen is :
(a) 1th first one tested (b) the 2nd one testedt
(b) the rd one tested (d) the last one tested


I am not sure but stem says that there are five pens places I I I I I
1 2 3 4 5
and if pick 1st or 2nd or third or last and test it the probability will remain same i.e. 1/5.

Kudos [?]: 170 [0], given: 0

Re: PSP001   [#permalink] 17 Oct 2008, 01:25
Display posts from previous: Sort by

One of 5 pens is faulty. They are tested one at a time, what

  post reply Question banks Downloads My Bookmarks Reviews Important topics  


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

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

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®.