GMAT Question of the Day: Daily via email | Daily via Instagram New to GMAT Club? Watch this Video

 It is currently 01 Jun 2020, 06:04

### 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

# M18-18

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 64153

### Show Tags

16 Sep 2014, 00:03
3
14
00:00

Difficulty:

55% (hard)

Question Stats:

58% (01:20) correct 42% (01:21) wrong based on 310 sessions

### HideShow timer Statistics

If 25% of the company's employees contribute at least 4% of their salary to the Charity Fund, what percent of the company's employees contribute at least 5% of their salary to the Charity Fund?

(1) 20% of the company's employees contribute at least 4% but less than 5% of their salary to the Charity Fund

(2) 95% of the company's employees contribute less than 5% of their salary to the Charity Fund

_________________
Math Expert
Joined: 02 Sep 2009
Posts: 64153

### Show Tags

16 Sep 2014, 00:03
3
1
4
Official Solution:

If 25% of the company's employees contribute at least 4% of their salary to the Charity Fund, what percent of the company's employees contribute at least 5% of their salary to the Charity Fund?

Say:

X% contribute less than 4%;

Y% contribute at least 4% but less than 5%;

Z% contribute at least 5%.

Note that these groups don't have intersections and $$X+Y+Z=100$$.

Given: $$Y+Z=25\%$$. Question: $$Z=$$?

(1) 20% of the company's employees contribute at least 4% but less than 5% of their salary to the Charity Fund. Given: $$Y=20\%$$. Hence, $$Y+Z=20+Z=25\%$$, which gives $$Z=5\%$$. Sufficient.

(2) 95% of the company's employees contribute less than 5% of their salary to the Charity Fund. Given: $$X+Y=95\%$$. Hence, $$X+Y+Z=95+Z=100\%$$, which gives $$Z=5\%$$. Sufficient.

_________________
##### General Discussion
Manager
Joined: 27 Jan 2013
Posts: 172
Location: United States
Concentration: Entrepreneurship, Marketing
GMAT 1: 730 Q49 V40
GPA: 3.5
WE: Supply Chain Management (Telecommunications)

### Show Tags

17 Feb 2015, 10:47
1
Bunuel

Requesting you to clarify my doubt. In this question are we not assuming that every employee is making a donation.

lets assume there are 100 people. Then we know that 25 of them contribute >=4%...

From 2 we know that 95% contribute <=5%...

Can we not consider a possibility that the 25 employees contribute more than 4 and less than 5 are part of the 95% who contribute less than 5%.. In this possibility we will come to conclusion that 5% of the people are not making any contribution..
Math Expert
Joined: 02 Sep 2009
Posts: 64153

### Show Tags

18 Feb 2015, 03:14
2
1
qw1981 wrote:
Bunuel

Requesting you to clarify my doubt. In this question are we not assuming that every employee is making a donation.

lets assume there are 100 people. Then we know that 25 of them contribute >=4%...

From 2 we know that 95% contribute <=5%...

Can we not consider a possibility that the 25 employees contribute more than 4 and less than 5 are part of the 95% who contribute less than 5%.. In this possibility we will come to conclusion that 5% of the people are not making any contribution..

X% of the employees who contribute less than 4 include those employees who did not contribute at all (contribute 0<4).

Check other discussions of this question:
if-25-of-the-company-s-employees-contribute-at-least-4-of-their-191729.html
if-25-of-the-company-s-employees-contribute-at-least-4-of-108484.html

Hope it helps.
_________________
Intern
Joined: 14 Jun 2014
Posts: 5

### Show Tags

30 Dec 2015, 06:30
I think this is a poor-quality question and I don't agree with the explanation. what about the ones that don't contribute at all ?
Math Expert
Joined: 02 Sep 2009
Posts: 64153

### Show Tags

30 Dec 2015, 08:22
1
deospaima wrote:
I think this is a poor-quality question and I don't agree with the explanation. what about the ones that don't contribute at all ?

X% of the employees who contribute less than 4 include those employees who did not contribute at all (contribute 0<4).

You just did not understand question/solution.
_________________
Current Student
Joined: 26 Feb 2018
Posts: 50
Location: India
GMAT 1: 640 Q45 V34
GPA: 3.9
WE: Web Development (Computer Software)

### Show Tags

18 Apr 2018, 13:24
I think this is a high-quality question and I agree with explanation. I do agree that this is a good quality question, but it takes a little time to understand the flaw in the thought process which made me reject choice B. All thanks to Bunuel! Thanks man!
Intern
Joined: 13 Jul 2018
Posts: 12
Location: India
Concentration: General Management, Strategy
WE: Information Technology (Journalism and Publishing)

### Show Tags

26 Jul 2018, 07:21
How can one assume that there are no intersections?
Manager
Joined: 31 Jul 2017
Posts: 191
Location: India
GMAT 1: 500 Q47 V15
GPA: 3.4
WE: Information Technology (Computer Software)

### Show Tags

15 Aug 2018, 00:45
20Hobbit wrote:
How can one assume that there are no intersections?

Selection of sets (X, Y & Z) have been done in such a way that there is no intersection. Please read carefully.

X% contribute less than 4%;

Y% contribute at least 4% but less than 5%;

Z% contribute at least 5%.

X+Y+Z=100.
Re: M18-18   [#permalink] 15 Aug 2018, 00:45

# M18-18

Moderators: chetan2u, Bunuel