Sponsored Ad:
Results 1 to 8 of 8

Thread: GMAT Prep Set theory Problem

  1. #1
    Within my grasp!
    Join Date
    Jan 2007
    Posts
    115
    Rep Power
    13


    Good post? Yes | No

    GMAT Prep Set theory Problem

    Sponsored Ad:
    Of the 200 members of a certain association, each member who speaks german also speaks english, and 70 of the members speak only spanish. if no member speaks all three languages, how many of the members speak two of the three languages?

    (1) 60 of the members speak only english.
    (2) 20 of the members do not speak any of the three languages.

  2. #2
    Within my grasp!
    Join Date
    Jan 2007
    Posts
    115
    Rep Power
    13


    Good post? Yes | No
    Any takers?

  3. #3
    Within my grasp!
    Join Date
    Sep 2006
    Posts
    413
    Rep Power
    14


    Good post? Yes | No
    Emphasis is that nobody speaks all three language.
    Combining I and II

    So, there cant be Sp and English speaker as we know some germans speak english.

    Draw a venn diagram and you will see Spanish circle standing alone while German one is enclosed in English.
    So we need to find how many people speak German.
    200 - 20 = 60 + 70 + German [they speak English as well]
    German = 180 - 130

    C.

  4. #4
    Eager! winjeemat's Avatar
    Join Date
    Oct 2007
    Location
    Pune, India
    Posts
    99
    Rep Power
    12


    Good post? Yes | No
    Quote Originally Posted by mbawannabe View Post
    Emphasis is that nobody speaks all three language.
    Combining I and II

    So, there cant be Sp and English speaker as we know some germans speak english.

    Draw a venn diagram and you will see Spanish circle standing alone while German one is enclosed in English.
    So we need to find how many people speak German.
    200 - 20 = 60 + 70 + German [they speak English as well]
    German = 180 - 130

    C.
    IMO the bolded text is not correct. Since all members who spk English(E) do not spk German(G), there would be some members who would spk both English and Spanish (S). Moreover, the Q stem is asking about how many members speak two of the three languages. Symbolically we need to find out the value of

    N(S & G only) + N(S & E only) + N(G & E only) ........where N denotes no of memebrs.

    Given .....N(S & G only) = 0.... &.... N(S & G & E) = 0


    St 1 & St 2:

    N(S or G or E) = N(only S) + N(only G) + N(only E) + N (G&E only) + N(S&E only) + N (S&G only) + N (S & G & E)

    200-20 .........= ...70 ......+ ...0........ + .....60.... + N(G & E only) + N(S& E only) + .......0 ........+ .........0.......

    N(S &E only) + N(G & E only) = 50 ........SUFF

    Ans IMO C

  5. #5
    Within my grasp!
    Join Date
    Jul 2008
    Posts
    373
    Rep Power
    13


    Good post? Yes | No
    Quote Originally Posted by B-Guru View Post
    Of the 200 members of a certain association, each member who speaks german also speaks english, and 70 of the members speak only spanish. if no member speaks all three languages, how many of the members speak two of the three languages?

    (1) 60 of the members speak only english.
    (2) 20 of the members do not speak any of the three languages.
    Can someone help to explain and solve this DS problem again .... thanks ....

  6. #6
    Within my grasp!
    Join Date
    Jul 2008
    Posts
    373
    Rep Power
    13


    Good post? Yes | No
    Quote Originally Posted by winjeemat View Post
    IMO the bolded text is not correct. Since all members who spk English(E) do not spk German(G), there would be some members who would spk both English and Spanish (S). Moreover, the Q stem is asking about how many members speak two of the three languages. Symbolically we need to find out the value of

    N(S & G only) + N(S & E only) + N(G & E only) ........where N denotes no of memebrs.

    Given .....N(S & G only) = 0.... &.... N(S & G & E) = 0


    St 1 & St 2:

    N(S or G or E) = N(only S) + N(only G) + N(only E) + N (G&E only) + N(S&E only) + N (S&G only) + N (S & G & E)

    200-20 .........= ...70 ......+ ...0........ + .....60.... + N(G & E only) + N(S& E only) + .......0 ........+ .........0.......

    N(S &E only) + N(G & E only) = 50 ........SUFF

    Ans IMO C
    How did you conclude that N(S & G only) = 0....

  7. #7
    Trying to make mom and pop proud
    Join Date
    Jun 2012
    Posts
    1
    Rep Power
    8


    Good post? Yes | No

    Thumbs up The answer is 50.

    Quote Originally Posted by gmatcraze View Post
    How did you conclude that N(S & G only) = 0....
    He comes to conclusion that (S&G)=0 because in the problem it says everyone who speaks german speaks english. And Their is no one who speaks all the three.

    If S&G !=0 then it will contradict the given data. So 50 is correct

  8. #8
    Trying to make mom and pop proud
    Join Date
    Aug 2012
    Location
    Dubai, United Arab Emirates, United Arab Emirates
    Posts
    7
    Rep Power
    8


    Good post? Yes | No
    IMO c

    Both statements are needed

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. DS problem set theory
    By ameyal in forum GMAT Problem Solving
    Replies: 0
    Last Post: 09-29-2007, 10:21 AM
  2. set theory problem Help!!
    By paam0101 in forum GMAT Problem Solving
    Replies: 1
    Last Post: 04-05-2007, 01:24 AM
  3. problem related to set theory !!
    By shruti_vip in forum GRE Computer Science
    Replies: 4
    Last Post: 07-27-2006, 08:06 AM
  4. Another GMAT prep set
    By Mohsin8 in forum GMAT Math
    Replies: 6
    Last Post: 06-12-2006, 07:28 PM
  5. Set theory problem
    By rajansays in forum GMAT Problem Solving
    Replies: 3
    Last Post: 03-11-2005, 05:42 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •