It is currently 23 Nov 2017, 04:48

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

Students in certain group know either English or French or both. If 20

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Intern
Intern
User avatar
Joined: 05 Jan 2016
Posts: 7

Kudos [?]: 18 [0], given: 9

Students in certain group know either English or French or both. If 20 [#permalink]

Show Tags

New post 10 Jan 2016, 05:22
1
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  75% (hard)

Question Stats:

53% (03:01) correct 47% (02:03) wrong based on 38 sessions

HideShow timer Statistics

Students in certain group know either English or French or both. If 20% of those who know English do not know French, and 60% of those who know French know English, what part of the entire group knows both languages?


A) 1/2
B) 12/23
C) 23/35
D) 13/27
E) 1/5
[Reveal] Spoiler: OA

Last edited by ENGRTOMBA2018 on 10 Jan 2016, 11:27, edited 1 time in total.
Reformatted the question

Kudos [?]: 18 [0], given: 9

Expert Post
Math Expert
User avatar
P
Joined: 02 Aug 2009
Posts: 5229

Kudos [?]: 5882 [0], given: 118

Re: Students in certain group know either English or French or both. If 20 [#permalink]

Show Tags

New post 10 Jan 2016, 05:43
TeymurHajiyev wrote:
Students in certain group know either English or French or both. If 20% of those who know English do not know French, and 60% of those who know French know English, what part of the group knows both languages?


Sorry guys, for constantly bothering you with this overlapping sets things. I promise, this would be the last one ;-)



Hi,
Again, venn diag would make it easy to comprehend..

let students who Know only english =E..
let students who Know only french =F..
let students who Know both english and french = B..

total =E+F+B..
1) If 20% of those who know English do not know French..
this means that 30% of students knowing english is B..
E=.2(E+B)...
2B=8E..
\(E=B/4\)...(i)

2)60% of those who know French know English
this means that 60% of students knowing French is B.
B=.6(F+B)..
\(F=\frac{4B}{6}\)..(ii)

add values found in (i) and (ii) in total..
so \(Total=E+F+B=\frac{B}{4}+ \frac{4B}{6} + B= \frac{23}{12} * B\)...

so \(\frac{23}{12} * B=T\)...
B=12/23 of total... ans

Doesn't matter .. you can ask till you clear your doubts...
someone will surely answer them
_________________

Absolute modulus :http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html

Kudos [?]: 5882 [0], given: 118

1 KUDOS received
Current Student
avatar
B
Joined: 20 Mar 2014
Posts: 2676

Kudos [?]: 1775 [1], given: 794

Concentration: Finance, Strategy
Schools: Kellogg '18 (M)
GMAT 1: 750 Q49 V44
GPA: 3.7
WE: Engineering (Aerospace and Defense)
GMAT ToolKit User Premium Member Reviews Badge
Re: Students in certain group know either English or French or both. If 20 [#permalink]

Show Tags

New post 10 Jan 2016, 09:00
1
This post received
KUDOS
TeymurHajiyev wrote:
Students in certain group know either English or French or both. If 20% of those who know English do not know French, and 60% of those who know French know English, what part of the group knows both languages?


Sorry guys, for constantly bothering you with this overlapping sets things. I promise, this would be the last one ;-)


Couple of points before I delve into your question:

1. Make sure to mention the complete question with all the options.

2. Follow posting guidelines including proper tags for the questions and do make sure to search for your questions before you post a new question.

Refer to the picture below

Attachment:
2016-01-10_10-56-43.jpg
2016-01-10_10-56-43.jpg [ 29.19 KiB | Viewed 779 times ]


Text in black is assumed/given and text in red is calculated.

From the common area (both english and french) ---> 0.8E = 0.6F ---> 4E=3F ...(1)

Additionally, T=E+0.4F = E+(8/15)E = (23/15)E ....(2)

Additionally, fraction of total group that knows both English and French = 0.8E = 0.8*(15/23) T = (12/23) T or just less than 50% of the total students.

Hope this helps.

Kudos [?]: 1775 [1], given: 794

Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 15530

Kudos [?]: 283 [0], given: 0

Premium Member
Re: Students in certain group know either English or French or both. If 20 [#permalink]

Show Tags

New post 25 Oct 2017, 09:08
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Kudos [?]: 283 [0], given: 0

Re: Students in certain group know either English or French or both. If 20   [#permalink] 25 Oct 2017, 09:08
Display posts from previous: Sort by

Students in certain group know either English or French or both. If 20

  new topic 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®.