BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

Set theory/Venn diagram prob

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 294
Joined: Tue Feb 26, 2008 9:05 pmFollowed by: 1 member
Thanked: 13 times
by amitansu » Mon May 05, 2008 10:41 pm
In a colony of 75 people, it's found that 35 people know only 2 of the three languages (German, Latin & French), While 10 people know all the three languages.If every person of the colony knows either of the 3 languages, then how many people know only one language ?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
User avatar
Legendary Member
Posts: 519
Joined: Sat Jan 27, 2007 7:56 am
Location: India
Thanked: 31 times

by Neo2000 » Tue May 06, 2008 12:13 am
10 ppl know all 3 languages

The Red section indicates ppl who know Only 2 languages and it is given that this = 35

The Green section indicates ppl who know only 1 language.

Out of 75 ppl, 10 know all 3 and 35 know 2 which means that 75 - (10+35) = 30 ppl know only 1 language.
Attachments
btg.JPG
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 294
Joined: Tue Feb 26, 2008 9:05 pmFollowed by: 1 member
Thanked: 13 times

by amitansu » Tue May 06, 2008 12:29 am
Nice lucid analysis Neo 2000 !!

My interpretation was wrong, i was taking 35 as intersection pf any two of the languages, i.e I took G and L = 35 and you know all wrong attempts after that !!

Thank you very much.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Legendary Member
Posts: 566
Joined: Fri Jan 04, 2008 11:01 am
Location: Philadelphia
Thanked: 31 times
GMAT Score:640

by AleksandrM » Tue May 06, 2008 9:46 am
You don't really need a venn diagram for this one. If it said that x know german, y know latin, and z know french, and then w know all three, then how many etc etc etc. In this case it is as simple as subtraction. We are not told that there is group a of people that know neither, so we just ignore it. However, we wouldn't ignore the lack of this piece of information on a DS problem.

75 - 35 - 10 = 30.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1