GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 12 Nov 2018, 14:35

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 in November
PrevNext
SuMoTuWeThFrSa
28293031123
45678910
11121314151617
18192021222324
2526272829301
Open Detailed Calendar
  • Essential GMAT Time-Management Hacks

     November 14, 2018

     November 14, 2018

     08:00 PM MST

     09:00 PM MST

    Join the webinar and learn time-management tactics that will guarantee you answer all questions, in all sections, on time. Save your spot today! Nov. 14th at 7 PM PST
  • $450 Tuition Credit & Official CAT Packs FREE

     November 15, 2018

     November 15, 2018

     10:00 PM MST

     11:00 PM MST

    EMPOWERgmat is giving away the complete Official GMAT Exam Pack collection worth $100 with the 3 Month Pack ($299)

When Professor Wang looked at the rosters for this term's

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

Hide Tags

Intern
Intern
avatar
Joined: 24 Nov 2012
Posts: 12
When Professor Wang looked at the rosters for this term's  [#permalink]

Show Tags

New post Updated on: 30 Sep 2014, 02:45
10
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

69% (02:02) correct 31% (02:43) wrong based on 276 sessions

HideShow timer Statistics

When Professor Wang looked at the rosters for this term's classes, she saw that the roster for her economics class (E) had 26 names, the roster for her marketing class (M) had 28, and the roster for her statistics class (S) had 18. When she compared the rosters, she saw that E and M had 9 names in common, E and S had 7, and M and S had 10. She also saw that 4 names were on all 3 rosters. If the rosters for Professor Wang's 3 classes are combined with no student's name listed more than once, how many names will be on the combined roster?

A. 30
B. 34
C. 42
D. 46
E. 50

Originally posted by saxenarahul021 on 27 Nov 2012, 00:20.
Last edited by Bunuel on 30 Sep 2014, 02:45, edited 2 times in total.
Renamed the topic and edited the tags.
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 50544
Re: When Professor Wang looked at the rosters for this term's  [#permalink]

Show Tags

New post 27 Nov 2012, 02:48
saxenarahul021 wrote:
When Professor Wang looked at the rosters for this term's classes, she saw that the roster for her economics class (E) had 26 names, the roster for her marketing class (M) had 28, and the roster for her statistics class (S) had 18. When she compared the rosters, she saw that E and M had 9 names in common, E and S had 7, and M and S had 10. She also saw that 4 names were on all 3 rosters. If the rosters for Professor Wang's 3 classes are combined with no student's name listed more than once, how many names will be on the combined roster?

A. 30
B. 34
C. 42
D. 46
E. 50


Total # of students 26+28+18-(9+7+10)+4=50.

Answer: E.

For more check ADVANCED OVERLAPPING SETS PROBLEMS
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Manager
Manager
avatar
Joined: 26 Feb 2012
Posts: 101
Location: India
Concentration: General Management, Finance
WE: Engineering (Telecommunications)
Re: When Professor Wang looked at the rosters for this term's  [#permalink]

Show Tags

New post 15 Jan 2014, 19:11
Bunuel wrote:
saxenarahul021 wrote:
When Professor Wang looked at the rosters for this term's classes, she saw that the roster for her economics class (E) had 26 names, the roster for her marketing class (M) had 28, and the roster for her statistics class (S) had 18. When she compared the rosters, she saw that E and M had 9 names in common, E and S had 7, and M and S had 10. She also saw that 4 names were on all 3 rosters. If the rosters for Professor Wang's 3 classes are combined with no student's name listed more than once, how many names will be on the combined roster?

A. 30
B. 34
C. 42
D. 46
E. 50


Total # of students 26+28+18-(9+7+10)+4=50.

Answer: E.

For more check ADVANCED OVERLAPPING SETS PROBLEMS


Hi Bunuel
Lemme know why it is +4 rather than -4

Also please solve through ven-diagram actually my i got wrong while solving in ven diagram....

Rgds
Prasannajeet
Veritas Prep GMAT Instructor
User avatar
P
Joined: 16 Oct 2010
Posts: 8521
Location: Pune, India
Re: When Professor Wang looked at the rosters for this term's  [#permalink]

Show Tags

New post 15 Jan 2014, 20:40
2
2
prasannajeet wrote:
Bunuel wrote:
saxenarahul021 wrote:
When Professor Wang looked at the rosters for this term's classes, she saw that the roster for her economics class (E) had 26 names, the roster for her marketing class (M) had 28, and the roster for her statistics class (S) had 18. When she compared the rosters, she saw that E and M had 9 names in common, E and S had 7, and M and S had 10. She also saw that 4 names were on all 3 rosters. If the rosters for Professor Wang's 3 classes are combined with no student's name listed more than once, how many names will be on the combined roster?

A. 30
B. 34
C. 42
D. 46
E. 50


Total # of students 26+28+18-(9+7+10)+4=50.

Answer: E.

For more check ADVANCED OVERLAPPING SETS PROBLEMS


Hi Bunuel
Lemme know why it is +4 rather than -4

Also please solve through ven-diagram actually my i got wrong while solving in ven diagram....

Rgds
Prasannajeet


When making the Venn diagram here, start by putting in the number of students which are in all 3 sets i.e. 4
Next, E and M had 9 names in common so the overlap of E and M excluding the overlap of all 3 will be 9 - 4 = 5.
Similarly for the E and S overlap and M and S overlap.
Next, E has 26 people and after removing 5 + 4 + 3 = 12, we are left with 14 people who have taken only E. Similarly for M and S too.

Attachment:
Ques3.jpg
Ques3.jpg [ 15.92 KiB | Viewed 5185 times ]


Now add all the students in the venn diagram = 14 + 5 + 13 + 3+ 4 + 6 + 5 = 50
_________________

Karishma
Veritas Prep GMAT Instructor

Learn more about how Veritas Prep can help you achieve a great GMAT score by checking out their GMAT Prep Options >

GMAT self-study has never been more personalized or more fun. Try ORION Free!

Intern
Intern
avatar
Joined: 15 May 2014
Posts: 24
Re: When Professor Wang looked at the rosters for this term's  [#permalink]

Show Tags

New post 30 Sep 2014, 02:44
3
it's easier and more efficient to use the formula rather than a venn diagram in the actual exam.

For this problem, the appropriate formula should be:
Total = Group 1 + Group 2 + Group 3 - (Sum of two group overlaps) + All three + Neither
Total = 26 + 28 + 18 - (9 + 7 + 10) + 4 + 0 = 50

FYI, if a question asks for "Exactly" two groups, the formula is slightly modified:
Total = Group 1 + Group 2 + Group 3 - (Sum of Exactly 2 group overlaps) - (2 x All Three) + Neither
SVP
SVP
User avatar
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1827
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: When Professor Wang looked at the rosters for this term's  [#permalink]

Show Tags

New post 01 Oct 2014, 00:13
It takes more time to read the problem, otherwise the Venn diagram is quite straightforward

Total students = 26 + (5+6) + 13 = 50

Answer = E
_________________

Kindly press "+1 Kudos" to appreciate :)

Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 8737
Premium Member
Re: When Professor Wang looked at the rosters for this term's  [#permalink]

Show Tags

New post 29 Mar 2018, 18:17
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

GMAT Club Bot
Re: When Professor Wang looked at the rosters for this term's &nbs [#permalink] 29 Mar 2018, 18:17
Display posts from previous: Sort by

When Professor Wang looked at the rosters for this term's

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| 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®.