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

It is currently 18 May 2013, 03:13
Customize  |  Hide

A fisherman caught 4000 fish. He marked at least 1/4 of the

  Question banks Downloads My Bookmarks Reviews  
Author Message
TAGS:
Manager
Manager
User avatar
Joined: 28 Nov 2004
Posts: 77
Followers: 1

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

A fisherman caught 4000 fish. He marked at least 1/4 of the [#permalink] New post 19 Dec 2004, 10:52
A fisherman caught 4000 fish. He marked at least 1/4 of the fish with a single mark. He also marked 400 fishes with two or more marks. What is the probability that the fisherman will catch a fish with a single mark among all the marked fishes?

I do not have the answer choices. Please explain your answer.
Manager
Manager
User avatar
Joined: 24 Aug 2004
Posts: 66
Followers: 1

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

 [#permalink] New post 19 Dec 2004, 12:40
Quote:
A fisherman caught 4000 fish. He marked at least 1/4 of the fish with a single mark. He also marked 400 fishes with two or more marks. What is the probability that the fisherman will catch a fish with a single mark among all the marked fishes?


Did you actually mean "at least" in the question. If that is the case, i dont think u can solve the problem,

Assuming the question meant exactly 1/4.
then Fishes with one mark = 1000.
fishes with 2 or more = 400.

so reqd probability = 1000/(1000 + 400) = 10/14 = 5/7.

If the question actually meant atleast 1/4. then it can be any number greater than 1000. so if the number of single marked fishes is 1/2 the answer wud be 2000/24000 = 5/6.

you can have effectively 1000 to 3600 as the number of single marked fishes. and each of these will give you a different probability.
Intern
Intern
Joined: 05 Dec 2004
Posts: 10
Followers: 0

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

 [#permalink] New post 19 Dec 2004, 12:41
unless theres a catch to this question or im not reading it right

1/4 marked with one mark = 1/4 of 4000 = 1000 fishes

400 fishes with 2 or more marks

so total marked fishes = 1400 of which reqd prob is 1000/1400 = 10/14

but i doubt the question is that easy....

what od u guys think ....71.5 percent or 0.715
Manager
Manager
User avatar
Joined: 28 Nov 2004
Posts: 77
Followers: 1

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

 [#permalink] New post 19 Dec 2004, 16:02
Sargataur wrote:
unless theres a catch to this question or im not reading it right

1/4 marked with one mark = 1/4 of 4000 = 1000 fishes

400 fishes with 2 or more marks

so total marked fishes = 1400 of which reqd prob is 1000/1400 = 10/14

but i doubt the question is that easy....

what od u guys think ....71.5 percent or 0.715


target780, Sargataur,

Yes, the word 'at least 1/4' is part of the question stem [I am dead sure about this]. And No the answer is NOT 5/7 since this was "not" one of the five answer choices.
I too believe having 'at least' makes the problem unbounded and therefore this makes a good tricky problem which the ETS loves to throw into the questions.

Can anyone else give this problem a try.
Manager
Manager
Joined: 29 Jul 2004
Posts: 64
Followers: 1

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

 [#permalink] New post 21 Dec 2004, 13:33
spiderman_xx wrote:
Sargataur wrote:
unless theres a catch to this question or im not reading it right

1/4 marked with one mark = 1/4 of 4000 = 1000 fishes

400 fishes with 2 or more marks

so total marked fishes = 1400 of which reqd prob is 1000/1400 = 10/14

but i doubt the question is that easy....

what od u guys think ....71.5 percent or 0.715


target780, Sargataur,

Yes, the word 'at least 1/4' is part of the question stem [I am dead sure about this]. And No the answer is NOT 5/7 since this was "not" one of the five answer choices.
I too believe having 'at least' makes the problem unbounded and therefore this makes a good tricky problem which the ETS loves to throw into the questions.

Can anyone else give this problem a try.


If this were a data sufficiency question I would say it is solvable, but it seems to be impossible to solve by hand. Since the probability is the number of favorable outcomes/total outcomes, you could add up the probability with 1/4 marked, then keep adding 1 more fish till you have all of them, or start with 0 marked, then go up to 1/4 and subtract 1 from this answer. Maybe there is some kind of pattern that would make any of these calculations possible but I don't know.

Was this problem in the OG? If so then do you know what number?
Manager
Manager
User avatar
Joined: 28 Nov 2004
Posts: 77
Followers: 1

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

 [#permalink] New post 21 Dec 2004, 13:44
toddmartin wrote:
spiderman_xx wrote:
Sargataur wrote:
unless theres a catch to this question or im not reading it right

1/4 marked with one mark = 1/4 of 4000 = 1000 fishes

400 fishes with 2 or more marks

so total marked fishes = 1400 of which reqd prob is 1000/1400 = 10/14

but i doubt the question is that easy....

what od u guys think ....71.5 percent or 0.715


target780, Sargataur,

Yes, the word 'at least 1/4' is part of the question stem [I am dead sure about this]. And No the answer is NOT 5/7 since this was "not" one of the five answer choices.
I too believe having 'at least' makes the problem unbounded and therefore this makes a good tricky problem which the ETS loves to throw into the questions.

Can anyone else give this problem a try.


If this were a data sufficiency question I would say it is solvable, but it seems to be impossible to solve by hand. Since the probability is the number of favorable outcomes/total outcomes, you could add up the probability with 1/4 marked, then keep adding 1 more fish till you have all of them, or start with 0 marked, then go up to 1/4 and subtract 1 from this answer. Maybe there is some kind of pattern that would make any of these calculations possible but I don't know.

Was this problem in the OG? If so then do you know what number?


toddmartin,
This was one of the questions that I got on my actual GMAT two weeks back. Of-course, the only rationale sol. I could get was 5/7, which was not one of the answer choices (I paniced). Therefore, I guessed.
Now, after seeing all of the responses, I guess this may have been an experimental question?
  [#permalink] 21 Dec 2004, 13:44
    Similar topics Author Replies Last post
Similar
Topics:
New posts In a certain pond, 50 fish were caught, tagged, and returned maverick_ucdc 2 28 Nov 2003, 06:49
New posts Q14: The Eurasian ruffe, a fish species inadvertently nakib77 6 22 Oct 2005, 05:58
New posts In a certain pond, 50 fish were caught, tagged, and returned SimaQ 2 02 Apr 2006, 02:37
New posts One fisheman was telling his friends that he caught a fish boubi 4 06 Jul 2007, 04:46
New posts 1 EXPERTS_POSTS_IN_THIS_TOPIC In a certain pond, 50 fish were caught, tagged, and returned DeeptiM 4 18 Aug 2011, 11:50
Display posts from previous: Sort by

A fisherman caught 4000 fish. He marked at least 1/4 of the

  Question banks Downloads My Bookmarks Reviews  


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®.