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

Redeem

100 people are attending a conference

Expert replies
by gmatdriller » Fri Jan 13, 2012 5:08 pm
100 people are attending a newspaper conference. 45 of them are writers
and more than 38 are editors. Of the people at the conference, x are
both writers and editors and 2x are neither. What is the largest possible
number of people who are both writers and editors?
A 6 B16 C 17 D 33 E84

Appreciate if you could use vennn diagram.
In solving the problem, kindly emphasize on the difference between
"editors" vs "only editors" or "writers" vs "non-writers"

Source ManhattanGmat cat6.

OAB
Join the discussion
Source: — Problem Solving |

by GMATGuruNY » Fri Jan 13, 2012 6:02 pm
gmatdriller wrote:100 people are attending a newspaper conference. 45 of them are writers
and more than 38 are editors. Of the people at the conference, x are
both writers and editors and 2x are neither. What is the largest possible
number of people who are both writers and editors?
A 6 B16 C 17 D 33 E84

Appreciate if you could use vennn diagram.
In solving the problem, kindly emphasize on the difference between
"editors" vs "only editors" or "writers" vs "non-writers"

Source ManhattanGmat cat6.

OAB
The quickest approach is to use the following formula:

Total = writers + editors - both + neither.

The big idea is to SUBTRACT the overlap.
When we count the total number of writers and the total number of editors, the OVERLAP -- everyone who is BOTH a writer and an editor -- is counted TWICE.
Thus, the people who are in BOTH groups must be subtracted from the total so that they are not double-counted.

In the equation above:
Total = 100.
Writers = 45.
Both = x.
Neither = 2x.

Plugging these values into the equation:
100 = 45 + editors - x + 2x
55 = editors + x.

In order to MAXIMIZE x, we need to MINIMIZE the number of editors.
Since more than 38 of the people are editors, the minimum number of editors = 39:
55 = 39 + x
x = 16.

The correct answer is B.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Join the discussion

by Anurag@Gurome » Fri Jan 13, 2012 6:10 pm
Image

The correct answer is B.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/
Join the discussion

by Neo Anderson » Fri Jan 13, 2012 6:17 pm
An alternate method:
Image

now you have 55-X > 38
=> X < 17 => Max value X can take is 16 hence B
Join the discussion

by gmatdriller » Sat Jan 14, 2012 9:03 am
i got it clearly, especially from the first two contributions.

Got confused as to how to represent "Editors" on the diagram, but the
ven diagram has explained it.

Thanks.
Join the discussion

by avigaggy » Tue Jan 31, 2012 10:00 pm
Hey hii guys .If this is the right answer then how would there be 32 ppl (2*16= 2*x)be neither of the writers or editors? where the question says that there are 45 writers and more than 38 editors.??
Join the discussion

by gmatdriller » Tue Jan 31, 2012 11:18 pm
avigaggy wrote:Hey hii guys .If this is the right answer then how would there be 32 ppl (2*16= 2*x)be neither of the writers or editors? where the question says that there are 45 writers and more than 38 editors.??
in the case at hand:
Writers: 45-16=29
Editors(more than 38):16+23=39 (Yes!)
Neither: 2*16 = 32
Total = 29+39+32 = 100
The number of Editors has to be more than 38 while Total must be 100.

Does that answer your question?
Join the discussion