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

It is currently 25 Sep 2018, 06:11

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

Each employee of a certain task force is either a manager or

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

Hide Tags

SVP
SVP
User avatar
Joined: 06 Sep 2013
Posts: 1796
Concentration: Finance
GMAT ToolKit User
Re: Each employee of a certain task force is either a manager or  [#permalink]

Show Tags

New post 25 Jan 2014, 09:18
Or one can solve this by using differentials

(1) and (2) together

We have that M = X-5000, and D = X+15,000

X being the total average so

-5000M+15000D = 0

The weights M,D are in a relation 1:3

So we know that 25% of the employers are directors

Hope it helps!
Cheers!
J :)
Veritas Prep GMAT Instructor
User avatar
P
Joined: 16 Oct 2010
Posts: 8298
Location: Pune, India
Each employee of a certain task force is either a manager or  [#permalink]

Show Tags

New post 19 Oct 2015, 22:12
1
kumarpritam wrote:
Each employee on a certain task force is either a manager or director. What percent of the employees on the task force are director?
1. The average (Arithmetic Mean) salary of the mangers on the task force is $5,000 less than the average salary of all employees on the task force.
2. The average (Arithmetic Mean) salary of the directors on the task force is $15,000 greater than the average salary of all employees on the task force.



The employees are a mix of managers and directors. We need to find the percentage of directors.

No statement alone gives you information on both managers and directors. We need to find whether both statements together are sufficient.

Use the scale method of weighted averages here.

w1/w2 = (A2 - Aavg)/(Aavg - A1) = 15000/5000 = 3:1
So for every 3 managers, there is one director. Hence, directors are 25% of the employees task force.
Answer (C)

Check this post for details of the scale method: http://www.veritasprep.com/blog/2011/03 ... -averages/
_________________

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: 07 Sep 2015
Posts: 11
Re: Data Sufficiency Question from GMAT Prep  [#permalink]

Show Tags

New post 19 Oct 2015, 22:24
Hi Kumarpritam,

Let the average salary of all the employees be $x.
Statement 1. the avg salary of the employees is $(x-5000) {Insufficient}
Statement 2. the avg salary of the directors is $(x+15000) {Insufficient}

Lets take S1 and S2 together. We can see that whatever may be the value of x, three employees salary would average out the salary of 1 director to have the average as x. [3*-5000 + 1*15000 = 0]
Hence, we can say that 25% are directors [1/(3+1)*100=1/4*100=25%] and rest 75% will be employees.

Answer C.

Let me know for any further clarification. Thanks.

P.S. Be kind and give Kudos. :D
Intern
Intern
avatar
Joined: 07 Sep 2015
Posts: 11
Re: Each employee of a certain task force is either a manager or  [#permalink]

Show Tags

New post 19 Oct 2015, 22:24
Instead of going for such long calculations, I think the best way to get on with this question is as follows:

Let the average salary of all the employees be $x.
Statement 1. the avg salary of the employees is $(x-5000) {Insufficient}
Statement 2. the avg salary of the directors is $(x+15000) {Insufficient}

Lets take S1 and S2 together. We can see that whatever may be the value of x, three employees salary would average out the salary of 1 director to have the average as x. [3*-5000 + 1*15000 = 0]
Hence, we can say that 25% are directors [1/(3+1)*100=1/4*100=25%] and rest 75% will be employees.

Answer C.

Let me know for any further clarification. Thanks.

P.S. Be kind and give Kudos. :D
Manager
Manager
avatar
B
Joined: 27 Aug 2015
Posts: 90
Re: Each employee of a certain task force is either a manager or  [#permalink]

Show Tags

New post 11 Sep 2016, 05:07
VeritasPrepKarishma wrote:
kumarpritam wrote:
Each employee on a certain task force is either a manager or director. What percent of the employees on the task force are director?
1. The average (Arithmetic Mean) salary of the mangers on the task force is $5,000 less than the average salary of all employees on the task force.
2. The average (Arithmetic Mean) salary of the directors on the task force is $15,000 greater than the average salary of all employees on the task force.



As Rich said, the right forum for this question is the DS forum.

The employees are a mix of managers and directors. We need to find the percentage of directors.

No statement alone gives you information on both managers and directors. We need to find whether both statements together are sufficient.

Use the scale method of weighted averages here.

w1/w2 = (A2 - Aavg)/(Aavg - A1) = 15000/5000 = 3:1
So for every 3 managers, there is one director. Hence, directors are 25% of the employees task force.
Answer (C)

Check this post for details of the scale method: http://www.veritasprep.com/blog/2011/03 ... -averages/


Hi Karishma, I also tried the same method for this but the ratio of 3:1 s the ration of average salary. How can we say that it would be the ratio of Managers and Directors?
Thanks
Veritas Prep GMAT Instructor
User avatar
P
Joined: 16 Oct 2010
Posts: 8298
Location: Pune, India
Re: Each employee of a certain task force is either a manager or  [#permalink]

Show Tags

New post 11 Sep 2016, 22:49
rakaisraka wrote:
VeritasPrepKarishma wrote:
kumarpritam wrote:
Each employee on a certain task force is either a manager or director. What percent of the employees on the task force are director?
1. The average (Arithmetic Mean) salary of the mangers on the task force is $5,000 less than the average salary of all employees on the task force.
2. The average (Arithmetic Mean) salary of the directors on the task force is $15,000 greater than the average salary of all employees on the task force.



As Rich said, the right forum for this question is the DS forum.

The employees are a mix of managers and directors. We need to find the percentage of directors.

No statement alone gives you information on both managers and directors. We need to find whether both statements together are sufficient.

Use the scale method of weighted averages here.

w1/w2 = (A2 - Aavg)/(Aavg - A1) = 15000/5000 = 3:1
So for every 3 managers, there is one director. Hence, directors are 25% of the employees task force.
Answer (C)

Check this post for details of the scale method: http://www.veritasprep.com/blog/2011/03 ... -averages/


Hi Karishma, I also tried the same method for this but the ratio of 3:1 s the ration of average salary. How can we say that it would be the ratio of Managers and Directors?
Thanks


How would you find the average salary of both - Managers + Directors

Average salary of group = (Avg sal of Managers * No of managers + Avg sal of Directors * No of Directors) / (No of Managers + No of Directors)

So note that the weights in weighted average formula are 'no of managers' and 'no of directors'.

The formula w1/w2 = (A2 - Aavg)/(Aavg - A1) is just an arrangement of the above formula.

w1 and w2 are the weights. A2 is the average salary of Directors, Aavg is the average salary of the group and A1 is the average salary of Managers.

Stmt. 1. The average (Arithmetic Mean) salary of the mangers on the task force is $5,000 less than the average salary of all employees on the task force.
This means Aavg - A1 = 5,000

Stmt 2. The average (Arithmetic Mean) salary of the directors on the task force is $15,000 greater than the average salary of all employees on the task force.
This means A2 - Aavg = 15,000
_________________

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!

Director
Director
User avatar
G
Joined: 26 Oct 2016
Posts: 648
Location: United States
Concentration: Marketing, International Business
Schools: HBS '19
GMAT 1: 770 Q51 V44
GPA: 4
WE: Education (Education)
Re: Each employee of a certain task force is either a manager or  [#permalink]

Show Tags

New post 30 Jan 2017, 18:03
1
Apply weighted Average formula:

N1/N2 = (M2-M)/(M-M1)

Let N1 = Managers
N2 = Directors

Statement 1: M-M1 = 5000
NOT SUFFICIENT

Statement 2: M2-M = 15000
NOT SUFFICIENT

Combining...

N1/N2 = 15000/5000 = 3:1

SUFFICIENT, SO [C]
_________________

Thanks & Regards,
Anaira Mitch

Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 8177
Premium Member
Re: Each employee of a certain task force is either a manager or  [#permalink]

Show Tags

New post 03 Feb 2018, 00:17
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: Each employee of a certain task force is either a manager or &nbs [#permalink] 03 Feb 2018, 00:17

Go to page   Previous    1   2   [ 28 posts ] 

Display posts from previous: Sort by

Each employee of a certain task force is either a manager or

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

Events & Promotions

PREV
NEXT


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®.