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

 It is currently 15 Nov 2018, 13:11

### 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

## Events & Promotions

###### Events & Promotions in November
PrevNext
SuMoTuWeThFrSa
28293031123
45678910
11121314151617
18192021222324
2526272829301
Open Detailed Calendar
• ### Free GMAT Strategy Webinar

November 17, 2018

November 17, 2018

07:00 AM PST

09:00 AM PST

Nov. 17, 7 AM PST. Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.
• ### GMATbuster's Weekly GMAT Quant Quiz # 9

November 17, 2018

November 17, 2018

09:00 AM PST

11:00 AM PST

Join the Quiz Saturday November 17th, 9 AM PST. The Quiz will last approximately 2 hours. Make sure you are on time or you will be at a disadvantage.

# M00-02

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

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 50613
M00-02  [#permalink]

### Show Tags

15 Sep 2014, 23:14
00:00

Difficulty:

15% (low)

Question Stats:

89% (01:41) correct 11% (02:17) wrong based on 38 sessions

### HideShow timer Statistics

Among the 750 employees of Massco Corporation 60% are women, and 90% are non-smokers. If 80% of the smokers are men, what is the number of female non-smokers?

A. 58
B. 240
C. 435
D. 450
E. 780

_________________
Math Expert
Joined: 02 Sep 2009
Posts: 50613
Re M00-02  [#permalink]

### Show Tags

15 Sep 2014, 23:14
Official Solution:

Among the 750 employees of Massco Corporation 60% are women, and 90% are non-smokers. If 80% of the smokers are men, what is the number of female non-smokers?

A. 58
B. 240
C. 435
D. 450
E. 780

* S N T M 8 32 40 W 2 58 60 T 10 90 100
Where M means men, W - women, S - smokers, N - nonsmokers, and T - total (100%). So, the percent we need is 58%.

Therefore, 0.58*750=435. On the GMAT, you don't need exact calculations, just take 0.6*750, which is 0.3*1,500 = a bit less than 450.

Answer: C
_________________
Intern
Joined: 31 Jan 2016
Posts: 4
Re: M00-02  [#permalink]

### Show Tags

07 Feb 2016, 15:55
I am confused to see 435 as the answer.

As i understand, among 750 employees 60% are women, that will be 450 women; which leaves 300 men.and if 90% of women are non-smokers that will be 90% of 450 which is 405. 450-405 = 45 women non-somokers; and 45 is 20% of 225, which means 225-45=180 men smokers account for 80% of the smokers

Men= 300, smokers 180, non-smokers 120
Women =450, smokers 45, non-smokers 405
Employees=750(300+450), Smokers 225(45+180), Non-smokers 525 (120+405)

Now smokers+ non-smokers equal to 525+225=750
Men + women =300+450 =750
Math Expert
Joined: 02 Aug 2009
Posts: 7034
Re: M00-02  [#permalink]

### Show Tags

07 Feb 2016, 17:41
1
aqeelnaqvi10 wrote:
I am confused to see 435 as the answer.

As i understand, among 750 employees 60% are women, that will be 450 women; which leaves 300 men.and if 90% of women are non-smokers that will be 90% of 450 which is 405. 450-405 = 45 women non-somokers; and 45 is 20% of 225, which means 225-45=180 men smokers account for 80% of the smokers

Men= 300, smokers 180, non-smokers 120
Women =450, smokers 45, non-smokers 405
Employees=750(300+450), Smokers 225(45+180), Non-smokers 525 (120+405)

Now smokers+ non-smokers equal to 525+225=750
Men + women =300+450 =750

Hi,
you are wrongly taking 90% of women to be non smokrs..
overall 90% are non smokers, which means 10% are smokers..
or .1*750=75 are smokers..

now 80% of the smokers are men..
.8*75=60..
so female smokers=75-60=15..

female nonsmokers=450-15=435..
HOpe it helps u
_________________

1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html

GMAT online Tutor

Manager
Joined: 24 Jan 2015
Posts: 72
GPA: 4
WE: Consulting (Pharmaceuticals and Biotech)
Re: M00-02  [#permalink]

### Show Tags

23 Apr 2018, 03:58
Bunuel wrote:
Official Solution:

Among the 750 employees of Massco Corporation 60% are women, and 90% are non-smokers. If 80% of the smokers are men, what is the number of female non-smokers?

A. 58
B. 240
C. 435
D. 450
E. 780

* S N T M 8 32 40 W 2 58 60 T 10 90 100
Where M means men, W - women, S - smokers, N - nonsmokers, and T - total (100%). So, the percent we need is 58%.

Therefore, 0.58*750=435. On the GMAT, you don't need exact calculations, just take 0.6*750, which is 0.3*1,500 = a bit less than 450.

Answer: C

I solved this question using the double set matrix. It took me about 1m45 secs.
I am unable to get the explanation provided here. Can someone help?
Study Buddy Forum Moderator
Joined: 04 Sep 2016
Posts: 1249
Location: India
WE: Engineering (Other)
M00-02  [#permalink]

### Show Tags

10 Jul 2018, 16:16
Bunuel chetan2u pushpitkc pikolo2510 Abhishek009 niks18

I tried to use double matrix method (black and blue : given; red: calculated; highlighted: final ans )
but the approach is too prone to make calculation errors. Is there any option to simplify the same?
>> !!!

You do not have the required permissions to view the files attached to this post.

_________________

It's the journey that brings us happiness not the destination.

PS Forum Moderator
Joined: 25 Feb 2013
Posts: 1217
Location: India
GPA: 3.82
Re: M00-02  [#permalink]

### Show Tags

11 Jul 2018, 08:18
1
adkikani wrote:
Bunuel chetan2u pushpitkc pikolo2510 Abhishek009 niks18

I tried to use double matrix method (black and blue : given; red: calculated; highlighted: final ans )
but the approach is too prone to make calculation errors. Is there any option to simplify the same?

Hi adkikani

I think matrix method is one of the easiest and quickest for these type of questions. Alternatively you can also use tree-structure method but it will have same level of calculation as the matrix method

Other way would be to simply treat it as a word problem and solve as per the given statements- step by step.
Re: M00-02 &nbs [#permalink] 11 Jul 2018, 08:18
Display posts from previous: Sort by

# M00-02

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

Moderators: chetan2u, Bunuel

 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®.