What is the median number of employees assigned per project : GMAT Data Sufficiency (DS)
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 20 Jan 2017, 09:22

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# What is the median number of employees assigned per project

Author Message
TAGS:

### Hide Tags

Intern
Joined: 03 Nov 2011
Posts: 11
Followers: 0

Kudos [?]: 35 [1] , given: 6

What is the median number of employees assigned per project [#permalink]

### Show Tags

04 May 2012, 01:20
1
KUDOS
37
This post was
BOOKMARKED
00:00

Difficulty:

45% (medium)

Question Stats:

61% (02:03) correct 39% (01:06) wrong based on 1144 sessions

### HideShow timer Statistics

What is the median number of employees assigned per project for the projects at Company Z?

(1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project.
(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project
[Reveal] Spoiler: OA

Last edited by Bunuel on 04 May 2012, 01:26, edited 1 time in total.
Moved to DS subforum
Math Expert
Joined: 02 Sep 2009
Posts: 36582
Followers: 7086

Kudos [?]: 93264 [12] , given: 10555

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

04 May 2012, 01:46
12
KUDOS
Expert's post
23
This post was
BOOKMARKED
ITIZCODE wrote:
What is the median number of employees assigned per project for the projects at Company Z?

(1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project.
(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project

What is the median number of employees assigned per project for the projects at Company Z?

(1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project. Not sufficient on its own.

(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project. Not sufficient on its own.

(1)+(2) Since 35% of of the projects have 2 or fewer ($$\leq{2}$$)employees and 25% of the projects have 4 or more ($$\geq{4}$$) employees, then 100%-(25%+35%)=40% of the projects have exactly 3 employees assigned to each of them. So, the median number of employees assigned per project is 3. Sufficient.

To elaborate more: consider there are 100 projects: $$\{p_1, \ p_2, \ ... , \ p_{100}\}$$. The values of $$p_1$$ to $$p_{35}$$ will be 0, 1, or 2; the values of $$p_{36}$$ to $$p_{75}$$ will be exactly 3; the values of $$p_{76}$$ to $$p_{100}$$ will be 4 or more. $$Median=\frac{p_{50}+p_{51}}{2}=\frac{3+3}{2}=3$$.

For example list can be: $$\{2, \ 2, \ 2, \ ..., \ (p_{35}=2), \ (p_{36}=3), \ 3, \ ..., \ (p_{75}=3), \ (p_{76}=4), \ 4, \ ..., \ (p_{100}=4)\}$$;
OR:
$$\{0, \ 0, \ 1, \ 1, \ 1, \ 2, \ 2, \ ..., \ (p_{35}=2), \ (p_{36}=3), \ 3, \ ..., \ (p_{75}=3), \ (p_{76}=4), \ 5, \ 7, \ 27, \ ..., \ (p_{100}=10000)\}$$ (of course there are a lot of other breakdowns).

In any case median=3.

Hope it's clear.

P.S. Please post PS questions in the PS subforum: gmat-problem-solving-ps-140/ and DS questions in the DS subforum: gmat-data-sufficiency-ds-141/ No posting of PS/DS questions is allowed in the main Math forum.
_________________
Director
Joined: 10 Mar 2013
Posts: 608
Location: Germany
Concentration: Finance, Entrepreneurship
GMAT 1: 580 Q46 V24
GPA: 3.88
WE: Information Technology (Consulting)
Followers: 15

Kudos [?]: 266 [3] , given: 200

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

20 Aug 2015, 13:36
3
KUDOS
2
This post was
BOOKMARKED
I've solved it this way (see attachment) -> the mid section of 40% =3 (it must be an integer, you cannot have fractions when dealing with persons So Statement 1+2 are sufficient (C)
Attachments

PS 139.png [ 22.89 KiB | Viewed 9301 times ]

_________________

When you’re up, your friends know who you are. When you’re down, you know who your friends are.

800Score ONLY QUANT CAT1 51, CAT2 50, CAT3 50
GMAT PREP 670
MGMAT CAT 630
KAPLAN CAT 660

Manager
Joined: 28 Jul 2011
Posts: 240
Followers: 3

Kudos [?]: 119 [2] , given: 16

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

06 May 2012, 15:08
2
KUDOS
Will vote for C

let total be "x" projects i.e 100% projec

(A) 25% projects has number of employees >= 4

- we dont know anything about other 75% projects

(B) 35% project has number of employees <= 2

- we dont know anything about other 65% projects

(C)

for 35% --> No. of emp <= 2
for 25% --> No. of emp >= 4

based on above data we can calculate that
Remaining 40% of projects --> No. of emp = 3 (which is between 2 < no. of emp < 4)
Intern
Joined: 10 Oct 2012
Posts: 4
Followers: 0

Kudos [?]: 2 [2] , given: 5

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

13 Apr 2013, 02:02
2
KUDOS
Aren't we assuming here that, statement 1 and 2 refer to highest 25 and bottom 35 percent of the employees, couldn't it be first 35 % then the next 25% and the remaining 40% with unknown number of employees per project, then the median will lie in 4 or more employees, we do not have any particular value and hence E as the correct answer.
VP
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1123
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Followers: 181

Kudos [?]: 1965 [2] , given: 219

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

13 Apr 2013, 02:14
2
KUDOS
1
This post was
BOOKMARKED
raxsin12 wrote:
Aren't we assuming here that, statement 1 and 2 refer to highest 25 and bottom 35 percent of the employees, couldn't it be first 35 % then the next 25% and the remaining 40% with unknown number of employees per project, then the median will lie in 4 or more employees, we do not have any particular value and hence E as the correct answer.

Statement 2 and 1 must refer to the bottom and to the highest part.
"couldn't it be first 35 % then the next 25% and the remaining 40%"? NO.
The first 35% have 2 or fewer (till here correct), but then your reasoning goes against the info in statement 1.
What you are saying is that 25%+40%=65% has 4 or more employees => wrong, look at statement 1:
(1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project.

Hope it's clear

P.S: Welcome to GMAT Club!
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

Senior Manager
Joined: 06 Aug 2011
Posts: 405
Followers: 2

Kudos [?]: 192 [1] , given: 82

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

11 Dec 2012, 02:47
1
KUDOS
roygush wrote:
What is the median number of employees assigned per project for the projects at Company Z?

(1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project.
(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project

Ruled out quickly A,B,D.
remained with C, E.
chose E.
then looked here:
what-is-the-median-number-of-employees-assigned-per-project-131892.html

and i still dont understand bunuel's way.
why the employees who are not in the 25% or 35% must have exactly 3 employees?
thanks

25% of company Z projects have 4 or more that (4,5,6,....)

35% of company z projects have 2 or less (0,1,2 )...

there must b 3 employees per project of company z which consists of (25+35=60) and 100-60=40%..

0,1,2 must be first 35 projects
3 employees for next 40 project
and 4 or more than 4 employees for remaning 25 projects..
_________________

Bole So Nehal.. Sat Siri Akal.. Waheguru ji help me to get 700+ score !

Intern
Joined: 24 Apr 2012
Posts: 48
Followers: 0

Kudos [?]: 22 [1] , given: 1

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

11 Dec 2012, 03:43
1
KUDOS
ITIZCODE wrote:
What is the median number of employees assigned per project for the projects at Company Z?

(1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project.
(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project

Ans: : Median is the middle value. Statements 1 and 2 alone give us insufficient data but when we combine both of them we see that 25 % have 4 or more and 35% have 2 or less therefore 40 %have 3 employees. Therefore the median would be 3 and the answer is (C).
_________________

www.mnemoniceducation.com

Math Expert
Joined: 02 Sep 2009
Posts: 36582
Followers: 7086

Kudos [?]: 93264 [1] , given: 10555

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

27 Dec 2012, 09:37
1
KUDOS
Expert's post
1
This post was
BOOKMARKED
rajathpanta wrote:
Bunuel wrote:
ITIZCODE wrote:
What is the median number of employees assigned per project for the projects at Company Z?

(1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project.
(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project

What is the median number of employees assigned per project for the projects at Company Z?

(1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project. Not sufficient on its own.

(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project. Not sufficient on its own.

(1)+(2) Since 35% of of the projects have 2 or fewer ($$\leq{2}$$)employees and 25% of the projects have 4 or more ($$\geq{4}$$) employees, then 100%-(25%+35%)=40% of the projects have exactly 3 employees assigned to each of them. So, the median number of employees assigned per project is 3. Sufficient.

To elaborate more: consider there are 100 projects: $$\{p_1, \ p_2, \ ... , \ p_{100}\}$$. The values of $$p_1$$ to $$p_{35}$$ will be 0, 1, or 2; the values of $$p_{36}$$ to $$p_{75}$$ will be exactly 3; the values of $$p_{76}$$ to $$p_{100}$$ will be 4 or more. $$Median=\frac{p_{50}+p_{51}}{2}=\frac{3+3}{2}=3$$.

For example list can be: $$\{2, \ 2, \ 2, \ ..., \ (p_{35}=2), \ (p_{36}=3), \ 3, \ ..., \ (p_{75}=3), \ (p_{76}=4), \ 4, \ ..., \ (p_{100}=4)\}$$;
OR:
$$\{0, \ 0, \ 1, \ 1, \ 1, \ 2, \ 2, \ ..., \ (p_{35}=2), \ (p_{36}=3), \ 3, \ ..., \ (p_{75}=3), \ (p_{76}=4), \ 5, \ 7, \ 27, \ ..., \ (p_{100}=10000)\}$$ (of course there are a lot of other breakdowns).

In any case median=3.

Hope it's clear.

P.S. Please post PS questions in the PS subforum: gmat-problem-solving-ps-140/ and DS questions in the DS subforum: gmat-data-sufficiency-ds-141/ No posting of PS/DS questions is allowed in the main Math forum.

I Did not understand this. How can you deduce about the 40% of the projects based on the information given. The problem just says 25% of the projects have 4 or more. 35% of the projects have 2 or less. So it does not talk anything about 40%. 40 % can be 5,6,7 or anything right?? Could you explain it in detail.

35 of the projects have 2 or fewer employees.
25 of the projects have 4 or more employees.

How many employees can be assigned to the remaining 40 projects? The ranges $$\leq{2}$$ and $$\geq{4}$$ are covered, thus the remaining 40 projects have 3 employees assigned to them.

Hope it's clear.
_________________
Manager
Joined: 13 Oct 2012
Posts: 78
Schools: IE '15 (A)
GMAT 1: 760 Q49 V46
Followers: 1

Kudos [?]: -12 [1] , given: 0

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

03 Jan 2013, 22:06
1
KUDOS
1st 35% are either 1 or 2 and last 25% are 4 and above
hence 35 - 75% should be 3
Manager
Joined: 18 May 2014
Posts: 63
Location: United States
Concentration: General Management, Other
GMAT Date: 07-31-2014
GPA: 3.99
WE: Analyst (Consulting)
Followers: 0

Kudos [?]: 12 [1] , given: 6

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

18 May 2014, 09:57
1
KUDOS
Statement (1) by itself is insufficient because we have no clue how the rest of the employees are assigned... same problem with statement (2).

When we combine the statement, we know that all the other projects have 3 employees assigned to each of them. If we were to write out the list, "3" would cover the middle terms, so it will end up being the median of the set.
Hence C.
Intern
Joined: 18 Aug 2012
Posts: 10
GMAT 1: 730 Q50 V39
Followers: 0

Kudos [?]: 5 [1] , given: 1

What is the median number of employees assigned per project [#permalink]

### Show Tags

28 Nov 2015, 05:46
1
KUDOS

Detailed Solution

Step-I: Given Info

The question asks us to find the median number of employees assigned per project for projects at Company Z, using the 2 statements given.

Step-II: Interpreting the Question Statement

To find the median number of employees, we need to somehow extract the central value for employees, when arranged in ascending order. Central value or median value will be the exact determination of value at the 50%th observation.

Step-III: Statement-I

Statement- I gives us the information about the 25% of projects have 4 or more employees assigned to each project.
Now let us say we have 100 projects. There could be a possibility that remaining 75 projects (>50 projects) have 3 employees. Then the central observation (50%th observation- in this case 50th project value in total 100 projects) will have a median value of 3 employees. But the remaining 75 projects can have 2 employees as well. Then the median will be 2. So we cannot determine with exact surety, the exact value of median at 50%th observation.

Hence, statement 1 is not sufficient to answer the question.

Step-IV: Statement-II

Statement- II gives us information that 35% of the projects have 2 or fewer employees assigned to each project. Now, the remaining 65 projects (>50 projects) can have 3 employees. Then the central observation (50%th observation- in this case 50th project value in total 100 projects) will have a median value of 3 employees. But the remaining 65 projects(>50 projects) can have a median value of 4 employees as well. Then the median value will be 4 employees. So we cannot determine with exact surety, the exact value of median at 50%th observation.

Hence, statement 2 is not sufficient to answer this question.

Step-V: Combining Statements I & II

When we combine both the statements we know the value of 25% of projects (4 or more employees) and 35% projects(2 or fewer employees). So the remaining 40 projects (<50 projects) will have 3 employees. When the observations are arranged in ascending order. The first 35 observations will have 2 or fewer employees and next 40 observations will have 3 employees and then next 25 observations will have 4 or more employees. Thus, the median number of employees will be 3.

Hence, the exact determination of central value or value at 50%th observation is 3.

So the correct answer is C. Both the statements together are sufficient.

Key Takeaways

Use of concept of median and evaluating all possible value of central value (median value) for observations to be able to find exact value at 50%th observation (when values arranged in ascending order).
Intern
Joined: 14 Aug 2012
Posts: 5
Followers: 0

Kudos [?]: 1 [0], given: 0

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

28 Aug 2012, 12:30
1
This post was
BOOKMARKED
Thanks for the reply! Finally got this one.
Manager
Status: exam is close ... dont know if i ll hit that number
Joined: 06 Jun 2011
Posts: 206
Location: India
GMAT Date: 10-09-2012
GPA: 3.2
Followers: 2

Kudos [?]: 22 [0], given: 1

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

30 Aug 2012, 19:42

i feel like i just cant do it without error
_________________

just one more month for exam...

Manager
Joined: 01 Sep 2012
Posts: 128
Followers: 1

Kudos [?]: 111 [0], given: 19

What is the median number of employees assigned per project [#permalink]

### Show Tags

10 Dec 2012, 13:11
What is the median number of employees assigned per project for the projects at Company Z?

(1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project.
(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project

Ruled out quickly A,B,D.
remained with C, E.
chose E.
then looked here:
what-is-the-median-number-of-employees-assigned-per-project-131892.html

and i still dont understand bunuel's way.
why the employees who are not in the 25% or 35% must have exactly 3 employees?
thanks
_________________

If my answer helped, dont forget KUDOS!

IMPOSSIBLE IS NOTHING

Senior Manager
Status: Prevent and prepare. Not repent and repair!!
Joined: 13 Feb 2010
Posts: 274
Location: India
Concentration: Technology, General Management
GPA: 3.75
WE: Sales (Telecommunications)
Followers: 9

Kudos [?]: 89 [0], given: 282

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

27 Dec 2012, 08:24
Bunuel wrote:
ITIZCODE wrote:
What is the median number of employees assigned per project for the projects at Company Z?

(1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project.
(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project

What is the median number of employees assigned per project for the projects at Company Z?

(1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project. Not sufficient on its own.

(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project. Not sufficient on its own.

(1)+(2) Since 35% of of the projects have 2 or fewer ($$\leq{2}$$)employees and 25% of the projects have 4 or more ($$\geq{4}$$) employees, then 100%-(25%+35%)=40% of the projects have exactly 3 employees assigned to each of them. So, the median number of employees assigned per project is 3. Sufficient.

To elaborate more: consider there are 100 projects: $$\{p_1, \ p_2, \ ... , \ p_{100}\}$$. The values of $$p_1$$ to $$p_{35}$$ will be 0, 1, or 2; the values of $$p_{36}$$ to $$p_{75}$$ will be exactly 3; the values of $$p_{76}$$ to $$p_{100}$$ will be 4 or more. $$Median=\frac{p_{50}+p_{51}}{2}=\frac{3+3}{2}=3$$.

For example list can be: $$\{2, \ 2, \ 2, \ ..., \ (p_{35}=2), \ (p_{36}=3), \ 3, \ ..., \ (p_{75}=3), \ (p_{76}=4), \ 4, \ ..., \ (p_{100}=4)\}$$;
OR:
$$\{0, \ 0, \ 1, \ 1, \ 1, \ 2, \ 2, \ ..., \ (p_{35}=2), \ (p_{36}=3), \ 3, \ ..., \ (p_{75}=3), \ (p_{76}=4), \ 5, \ 7, \ 27, \ ..., \ (p_{100}=10000)\}$$ (of course there are a lot of other breakdowns).

In any case median=3.

Hope it's clear.

P.S. Please post PS questions in the PS subforum: gmat-problem-solving-ps-140/ and DS questions in the DS subforum: gmat-data-sufficiency-ds-141/ No posting of PS/DS questions is allowed in the main Math forum.

I Did not understand this. How can you deduce about the 40% of the projects based on the information given. The problem just says 25% of the projects have 4 or more. 35% of the projects have 2 or less. So it does not talk anything about 40%. 40 % can be 5,6,7 or anything right?? Could you explain it in detail.
_________________

I've failed over and over and over again in my life and that is why I succeed--Michael Jordan
Kudos drives a person to better himself every single time. So Pls give it generously
Wont give up till i hit a 700+

Intern
Joined: 10 Oct 2012
Posts: 4
Followers: 0

Kudos [?]: 2 [0], given: 5

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

13 Apr 2013, 02:37
Thanks for the welcome and the explanation! Its clear now.....
Intern
Joined: 19 Oct 2013
Posts: 6
GMAT Date: 01-13-2014
Followers: 0

Kudos [?]: 2 [0], given: 2

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

19 Oct 2013, 10:02
1
This post was
BOOKMARKED
Hi,

i understand the answers, although i must say there is no information that says that no percentage has more than for example 5 employees per project. It could be possible to have a 25% with 4 or more, and from there a group that has 5 or more. Both equalities would still be right. For example a 25% thats has 4 or more, and only 15% that has 5 or more. A group within a group. I hope i made myself clear...
In that case the answer for me would be "e"

Intern
Joined: 19 Oct 2013
Posts: 6
GMAT Date: 01-13-2014
Followers: 0

Kudos [?]: 2 [0], given: 2

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

19 Oct 2013, 10:13
versuchmachtklug wrote:
Hi,

i understand the answers, although i must say there is no information that says that no percentage has more than for example 5 employees per project. It could be possible to have a 25% with 4 or more, and from there a group that has 5 or more. Both equalities would still be right. For example a 25% thats has 4 or more, and only 15% that has 5 or more. A group within a group. I hope i made myself clear...
In that case the answer for me would be "e"

JUST GOT IT!! saying it loud helped me..thanks anyways
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 13462
Followers: 575

Kudos [?]: 163 [0], given: 0

Re: What is the median number of employees assigned per project [#permalink]

### Show Tags

16 Jun 2015, 11:13
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.
_________________
Re: What is the median number of employees assigned per project   [#permalink] 16 Jun 2015, 11:13

Go to page    1   2    Next  [ 23 posts ]

Similar topics Replies Last post
Similar
Topics:
6 What is the median number of books purchased per student in 6 24 Mar 2014, 14:29
8 What is the median number of employees assigned per project 6 27 Jul 2011, 07:10
6 What is the median number of employees assigned per project 5 29 Jun 2011, 11:04
1 What is the median number of employees assigned per project 16 17 Apr 2010, 08:00
16 What is the median number of employees assigned per project 8 05 Jul 2008, 11:01
Display posts from previous: Sort by