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

 It is currently 20 Sep 2018, 21:50

### 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

# Currently, y percent of the members on the finance committee

Author Message
TAGS:

### Hide Tags

VP
Joined: 14 May 2006
Posts: 1361
Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

08 Aug 2006, 12:21
4
30
00:00

Difficulty:

85% (hard)

Question Stats:

60% (02:35) correct 40% (02:14) wrong based on 580 sessions

### HideShow timer Statistics

Currently, y percent of the members on the finance committee are women and next month, z percent of the men on the finance committee will resign. If no other personnel changes occur, then after the resignations next month, the men who remain on the finance committee will represent what percent of the total finance committee members?

A. $$\frac{100(100 - z)(100 - y)}{100^2 - z(100 - y)}$$

B. $$\frac{(100 - z)(100 - y)}{100}$$

C. $$(100 - z)(100 - y)$$

D. $$\frac{zy}{100} - z$$

E. $$\frac{z(100 - y)}{100}$$
Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 8282
Location: Pune, India
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

16 Jan 2014, 20:40
6
1
jlgdr wrote:
Let's say that there are a total of 100 members
Let's also say that y = 50
So there are 50 men
Now z = 10 so 45 men are left
(45/95)*100 = 9/19 *100 = 900/19

Target 900/19
Inputs
y=50
z=10

Only A gives the correct answer

Hope it helps
Cheers!
J

Yes, number plugging is the best choice here though I would take much easier numbers to reduce the time taken. Almost no calculations will be involved.

e.g. Say 50% are women i.e. y = 50 and say 100% of men will resign i.e. z = 100 so the correct option should give me 0. I see that z = 100 is not a problem because you don't have z - 100 anywhere in the denominators.
(A), (B) and (C) have z - 100 in the numerator so they will give us 0. (D) and (E) will not. So I will only worry about (A), (B) and (C).

Now say z = 50% i.e. the remaining men will be 25/75 = 1/3. Put z = 50 and y = 50 in (B) and (C) since they are simpler and you can just see what you will get without any calculations. Neither gives 33.33. Obviously, (A) will be the correct answer. You don't even need to plug in to check.

_________________

Karishma
Veritas Prep GMAT Instructor

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

##### General Discussion
CEO
Joined: 20 Nov 2005
Posts: 2824
Schools: Completed at SAID BUSINESS SCHOOL, OXFORD - Class of 2008
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

08 Aug 2006, 12:39
1
2
A

Current month:
Let total = 100
No. of females = y
No. of males = 100-y

Next month:
No of females = y
No of males = (100-y)*(100-z)/100
Total = y + (100-y)*(100-z)/100
= (100y + 100^2 - 100y -100z+yz)/100
= [100^2 - z(100-y)]/100

Percentage of males = [100 * (100-y)*(100-z)/100] / [100^2 - z(100-y)]/100
i.e (100)(100 â€“ z)(100 â€“ y)/100^2 â€“ z(100 â€“ y)
_________________

SAID BUSINESS SCHOOL, OXFORD - MBA CLASS OF 2008

VP
Joined: 29 Dec 2005
Posts: 1313
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

08 Aug 2006, 13:28
1
w = y
m = 100 - y
total = 100
m after z = (100 - y) - [z (100- y)/100] = (100-z)(100-y)/100
m (after z) as a % of total = [(100-z)(100-y)/100]/[{(100-y)(100-z)/100} + y] x [100]

after solviing for y and z: m (after z) as a % of total = [100 (100-z)(100-y)]/[(100^2 - z (100-y)]

its A. imo, plugging-in is best for such a tedious calculation.
Manager
Joined: 20 Mar 2006
Posts: 200
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

09 Aug 2006, 17:54
ps_dahiya wrote:
A

Current month:
Let total = 100
No. of females = y
No. of males = 100-y

Next month:
No of females = y
No of males = (100-y)*(100-z)/100
Total = y + (100-y)*(100-z)/100
= (100y + 100^2 - 100y -100z+yz)/100
= [100^2 - z(100-y)]/100

Percentage of males = [100 * (100-y)*(100-z)/100] / [100^2 - z(100-y)]/100
i.e (100)(100 â€“ z)(100 â€“ y)/100^2 â€“ z(100 â€“ y)

Ps: How are you getting 100-z/100 when Q says z% of the men. Wouldnt it be (100-y)*z/100

Heman
Manager
Joined: 07 Aug 2005
Posts: 114
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

09 Aug 2006, 20:41
heman wrote:
ps_dahiya wrote:
A

Current month:
Let total = 100
No. of females = y
No. of males = 100-y

Next month:
No of females = y
No of males = (100-y)*(100-z)/100
Total = y + (100-y)*(100-z)/100
= (100y + 100^2 - 100y -100z+yz)/100
= [100^2 - z(100-y)]/100

Percentage of males = [100 * (100-y)*(100-z)/100] / [100^2 - z(100-y)]/100
i.e (100)(100 â€“ z)(100 â€“ y)/100^2 â€“ z(100 â€“ y)

Ps: How are you getting 100-z/100 when Q says z% of the men. Wouldnt it be (100-y)*z/100

Heman

z pct men left, so the number of remaining men is 100-z pct of women.
SVP
Joined: 30 Mar 2006
Posts: 1696
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

11 Aug 2006, 03:04
4
For these questions..... I find it better to take some values for y and z

for example.
Let total finance commitee members = 100
Let y = 20 and z = 5

hence men left = 80 - 4 = 76

Percent = 7600/96

Now lets plug in values in the choices.
A = 100 * 95*80/10000 - 400
= 100 * 95*80/9600
= 7600/96
Magoosh GMAT Instructor
Joined: 28 Nov 2011
Posts: 305
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

18 Apr 2012, 15:46
1
Hi, I know this is an ancient thread but was just replying in response to one of Magoosh's users who had asked me to take a look.

The responses above are fine (check out ps-dahiya's). The thing with this problem is the algebraic solution is time-consuming and unwieldy. It is not that the users are missing a more elegant algebraic solution. The take away from a question such as this one - esp., if you want to answer it in under 2 minutes - is to plug in. @Jaynayak shows how to do so in his post.

Hope that helps .
_________________

Christopher Lele
Magoosh Test Prep

SVP
Joined: 06 Sep 2013
Posts: 1809
Concentration: Finance
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

16 Jan 2014, 16:00
1
1
Let's say that there are a total of 100 members
Let's also say that y = 50
So there are 50 men
Now z = 10 so 45 men are left
(45/95)*100 = 9/19 *100 = 900/19

Target 900/19
Inputs
y=50
z=10

Only A gives the correct answer

Hope it helps
Cheers!
J
Manager
Joined: 11 Sep 2013
Posts: 162
Concentration: Finance, Finance
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

24 Aug 2014, 12:33
Number Plug has worked very quickly.
Let Total =100, Y= 50 and Z = 10. So New no. of men = .90*50 =45, New no. of total =100-5 =95
Percent = (45/95)*100 = 900/19. Plug the y=50 and z= 10.
Remember, first plug in easy option. You will immediately find that in B, C, D and E you are not getting 19 in denominator. Ans-A
Intern
Joined: 05 Jun 2015
Posts: 25
Location: Viet Nam
GMAT 1: 740 Q49 V41
GPA: 3.66
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

02 Mar 2016, 21:55
VeritasPrepKarishma wrote:

Now say z = 50% i.e. the remaining men will be 25/75 = 1/3. Put z = 50 and y = 50 in (B) and (C) since they are simpler and you can just see what you will get without any calculations. Neither gives 33.33. Obviously, (A) will be the correct answer. You don't even need to plug in to check.

Hi Karishma,

I tried plugging numbers for option A, but somehow I cannot get 1/3.

$$\frac{{100*(100-50)*(100-50)}}{{100*100-50*(100-50)}}=\frac{{100*50*50}}{{100^2-50^2}}=\frac{{100*50*50}}{{50*150}}=\frac{5000}{150}$$

Could you please point out what is wrong with the above calculation?
Thank you very much!
Nhi
Manager
Joined: 11 Sep 2013
Posts: 162
Concentration: Finance, Finance
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

02 Mar 2016, 23:03
truongynhi wrote:
VeritasPrepKarishma wrote:

Now say z = 50% i.e. the remaining men will be 25/75 = 1/3. Put z = 50 and y = 50 in (B) and (C) since they are simpler and you can just see what you will get without any calculations. Neither gives 33.33. Obviously, (A) will be the correct answer. You don't even need to plug in to check.

Hi Karishma,

I tried plugging numbers for option A, but somehow I cannot get 1/3.

$$\frac{{100*(100-50)*(100-50)}}{{100*100-50*(100-50)}}=\frac{{100*50*50}}{{100^2-50^2}}=\frac{{100*50*50}}{{50*150}}=\frac{5000}{150}$$

Could you please point out what is wrong with the above calculation?
Thank you very much!
Nhi

You can look at my solution

Number Plug has worked very quickly.
Let Total =100, Y= 50 and Z = 10. So New no. of men = .90*50 =45, New no. of total =100-5 =95
Percent = (45/95)*100 = 900/19. Plug the y=50 and z= 10.

Remember, first plug the numbers in easy option. You will immediately find that in B, C, D and E you are not getting 19 in the denominator. Ans-A
Intern
Joined: 05 Jun 2015
Posts: 25
Location: Viet Nam
GMAT 1: 740 Q49 V41
GPA: 3.66
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

02 Mar 2016, 23:30
Raihanuddin wrote:
You can look at my solution

Number Plug has worked very quickly.
Let Total =100, Y= 50 and Z = 10. So New no. of men = .90*50 =45, New no. of total =100-5 =95
Percent = (45/95)*100 = 900/19. Plug the y=50 and z= 10.

Remember, first plug the numbers in easy option. You will immediately find that in B, C, D and E you are not getting 19 in the denominator. Ans-A

Hi Raihanuddin,
Thank you for the prompt reply. But you didn't address my question. I understood the plugging method and knew that B, C, D, and E are wrong. I am asking about the arithmetic operation when plugging z=y=50 into option A.
Intern
Joined: 09 Dec 2014
Posts: 5
WE: Information Technology (Health Care)
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

12 Apr 2017, 14:23
jaynayak wrote:
For these questions..... I find it better to take some values for y and z

for example.
Let total finance commitee members = 100
Let y = 20 and z = 5

hence men left = 80 - 4 = 76

Percent = 7600/96

Now lets plug in values in the choices.
A = 100 * 95*80/10000 - 400
= 100 * 95*80/9600
= 7600/96

I'm sure there is an obvious answer to this but why did you subtract by 4 and not 5
Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 8282
Location: Pune, India
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

13 Apr 2017, 04:11
chinelj wrote:
jaynayak wrote:
For these questions..... I find it better to take some values for y and z

for example.
Let total finance commitee members = 100
Let y = 20 and z = 5

hence men left = 80 - 4 = 76

Percent = 7600/96

Now lets plug in values in the choices.
A = 100 * 95*80/10000 - 400
= 100 * 95*80/9600
= 7600/96

I'm sure there is an obvious answer to this but why did you subtract by 4 and not 5

The question says "z percent of the men will resign."
If there are 80 men (assuming 20% are women and total employees are 100), then 5% of 80 is 4. That is why you subtract 4.
_________________

Karishma
Veritas Prep GMAT Instructor

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

Intern
Joined: 09 Mar 2017
Posts: 38
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

22 Jul 2017, 08:36
Can someone help me out why I am being such an idiot here? I can calculate the denominator but I get a slightly different answer for the numerator. Obviously I am missing something here, but I can't seem to figure it out.

Let's say:

T=Total
Y=W=Women
M=Men
Z=Men resigning

The # of men left over after men have resigned=
((100-y)/100) * T *((100-z)/100). I.e. (% of Men * Total)=# of Men * (% of Men Resigning).

The denominator= Women + men who haven't signed=
y/100*T + ((100-y)/100) * T *((100-z)/100)

Thus when I reduce this I get:
1. ((T)(100-y)(100-z))/100^2)/(((100*Y*T)/100^2)+((T)(100-y)(100-z))/100^2))

2. ((T)(100-y)(100-z))/100^2) / (((100*Y*T)+((100-y)(100-z)(t)))/100^2

3. ((T)(100-y)(100-z))/100^2) * 100^2/ (t)(100^2-z(100-y))

4. (100-y)(100-z))/(100^2-z(100-y))

What am I missing? Thanks!
Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 8282
Location: Pune, India
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

05 Aug 2017, 02:54
brandon7 wrote:
Can someone help me out why I am being such an idiot here? I can calculate the denominator but I get a slightly different answer for the numerator. Obviously I am missing something here, but I can't seem to figure it out.

Let's say:

T=Total
Y=W=Women
M=Men
Z=Men resigning

The # of men left over after men have resigned=
((100-y)/100) * T *((100-z)/100). I.e. (% of Men * Total)=# of Men * (% of Men Resigning).

The denominator= Women + men who haven't signed=
y/100*T + ((100-y)/100) * T *((100-z)/100)

Thus when I reduce this I get:
1. ((T)(100-y)(100-z))/100^2)/(((100*Y*T)/100^2)+((T)(100-y)(100-z))/100^2))

2. ((T)(100-y)(100-z))/100^2) / (((100*Y*T)+((100-y)(100-z)(t)))/100^2

3. ((T)(100-y)(100-z))/100^2) * 100^2/ (t)(100^2-z(100-y))

4. (100-y)(100-z))/(100^2-z(100-y))

What am I missing? Thanks!

When you convert something into a percentage, you multiply by 100. Say, 2 is what percent of 4?
2/4 * 100 = 50
So 2 is 50% of 4.

I think you have missed multiplying by 100 at the end.
_________________

Karishma
Veritas Prep GMAT Instructor

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

Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 8282
Location: Pune, India
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

05 Aug 2017, 03:14
1
brandon7 wrote:
Can someone help me out why I am being such an idiot here? I can calculate the denominator but I get a slightly different answer for the numerator. Obviously I am missing something here, but I can't seem to figure it out.

Let's say:

T=Total
Y=W=Women
M=Men
Z=Men resigning

The # of men left over after men have resigned=
((100-y)/100) * T *((100-z)/100). I.e. (% of Men * Total)=# of Men * (% of Men Resigning).

The denominator= Women + men who haven't signed=
y/100*T + ((100-y)/100) * T *((100-z)/100)

Thus when I reduce this I get:
1. ((T)(100-y)(100-z))/100^2)/(((100*Y*T)/100^2)+((T)(100-y)(100-z))/100^2))

2. ((T)(100-y)(100-z))/100^2) / (((100*Y*T)+((100-y)(100-z)(t)))/100^2

3. ((T)(100-y)(100-z))/100^2) * 100^2/ (t)(100^2-z(100-y))

4. (100-y)(100-z))/(100^2-z(100-y))

What am I missing? Thanks!

When you convert something into a percentage, you multiply by 100. Say, 2 is what percent of 4?
2/4 * 100 = 50
So 2 is 50% of 4.

I think you have missed multiplying by 100 at the end.
_________________

Karishma
Veritas Prep GMAT Instructor

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

Intern
Joined: 12 Feb 2017
Posts: 3
Re: Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

07 Aug 2017, 18:15
Here's an easier number, how about 0?

If there are zero percent women, and zero percent men that leave, you know that the answer you are looking for is 100. (Since no women are part of the set, and no men leave, you should have 100 percent men).

Only A and B result in 100 when plugged in. Now use some logic to weed out answer B, let's pretend z=1 (one percent men leave) but still y=0 (no women). B would give us 99 percent men, which is false since it is still ALL men (even if some leave).

Therefore, you are left with A.
Intern
Joined: 03 Apr 2017
Posts: 20
Currently, y percent of the members on the finance committee  [#permalink]

### Show Tags

30 Dec 2017, 05:11
VeritasPrepKarishma wrote:
jlgdr wrote:
Let's say that there are a total of 100 members
Let's also say that y = 50
So there are 50 men
Now z = 10 so 45 men are left
(45/95)*100 = 9/19 *100 = 900/19

Target 900/19
Inputs
y=50
z=10

Only A gives the correct answer

Hope it helps
Cheers!
J

Yes, number plugging is the best choice here though I would take much easier numbers to reduce the time taken. Almost no calculations will be involved.

e.g. Say 50% are women i.e. y = 50 and say 100% of men will resign i.e. z = 100 so the correct option should give me 0. I see that z = 100 is not a problem because you don't have z - 100 anywhere in the denominators.
(A), (B) and (C) have z - 100 in the numerator so they will give us 0. (D) and (E) will not. So I will only worry about (A), (B) and (C).

Now say z = 50% i.e. the remaining men will be 25/75 = 1/3. Put z = 50 and y = 50 in (B) and (C) since they are simpler and you can just see what you will get without any calculations. Neither gives 33.33. Obviously, (A) will be the correct answer. You don't even need to plug in to check.

Hello Karishma,

Unfortunately, I am not getting the correct answer. I tried the below:

total = 20 people
women = 10 men=10 z%=10

so 10*10/100=1 hence remaining men = 9

total is 9/19*100 = 900/19

A. 100(100−10)(100−10)
-------------------------- = 100*90*90/10000-900= 810000/9100 = 8100/91
100^2−10(100−10)

Can you help me where did I go wrong with this one? VeritasPrepKarishma

Best Regards,
Shrish
Currently, y percent of the members on the finance committee &nbs [#permalink] 30 Dec 2017, 05:11

Go to page    1   2    Next  [ 22 posts ]

Display posts from previous: Sort by

# Events & Promotions

 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®.