It is currently 19 Oct 2017, 15:41

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

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

A certain marathon had 20,000 entrants, 52% of which were female and 3

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

Hide Tags

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 41891

Kudos [?]: 128907 [0], given: 12183

A certain marathon had 20,000 entrants, 52% of which were female and 3 [#permalink]

Show Tags

New post 26 Jan 2017, 10:28
Expert's post
1
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  65% (hard)

Question Stats:

65% (01:41) correct 35% (02:07) wrong based on 111 sessions

HideShow timer Statistics

A certain marathon had 20,000 entrants, 52% of which were female and 30% of these female entrants were professional runners. If 60% of the entrants were professional, how many of the runners in the marathon were amateur male runners?

A. 72
B. 720
C. 3,120
D. 8,000
E. 8,880
[Reveal] Spoiler: OA

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Kudos [?]: 128907 [0], given: 12183

Director
Director
avatar
S
Joined: 21 Mar 2016
Posts: 530

Kudos [?]: 28 [0], given: 97

Reviews Badge CAT Tests
Re: A certain marathon had 20,000 entrants, 52% of which were female and 3 [#permalink]

Show Tags

New post 26 Jan 2017, 11:32
ans B 720

amatuer runners = 40% of 20000 = 8000
8000 minus the female amtuer runner will givve the answer

Kudos [?]: 28 [0], given: 97

Director
Director
User avatar
P
Joined: 05 Mar 2015
Posts: 964

Kudos [?]: 287 [0], given: 41

Re: A certain marathon had 20,000 entrants, 52% of which were female and 3 [#permalink]

Show Tags

New post 26 Jan 2017, 12:06
Bunuel wrote:
A certain marathon had 20,000 entrants, 52% of which were female and 30% of these female entrants were professional runners. If 60% of the entrants were professional, how many of the runners in the marathon were amateur male runners?

A. 72
B. 720
C. 3,120
D. 8,000
E. 8,880



No. of females = 52% of 20000 = 10400
Professional females = 30% of 10400 = 3120
Total professional(M+F) = 60% of 20000 =12000
thus male professional = total professional - female professional = 12000-3120 = 8880
amateur males = Total runners -(total females + professional male) = 20000- (10400+8880) =720

Ans B

Kudos [?]: 287 [0], given: 41

Manager
Manager
User avatar
S
Status: Math Tutor
Joined: 12 Aug 2017
Posts: 72

Kudos [?]: 29 [0], given: 13

WE: Education (Education)
Re: A certain marathon had 20,000 entrants, 52% of which were female and 3 [#permalink]

Show Tags

New post 14 Aug 2017, 12:16
Amateur Professional Total
Male 720(9600-8880) 8880(12000-3120) 9600(20000-10400)

Female 3120(30%*10400) 10400(52%*20000)

Total 12000(60%20000) 20000(given)

First calculate 52%
then calculate 30%
then calculate 60%
then subtract 20000 -10400 and also 12000-3120
then finally subtract 9600-720
_________________

Abhishek Parikh
Math Tutor
Whatsapp- +919983944321
Mobile- +971529685639
Website: http://www.holamaven.com

Kudos [?]: 29 [0], given: 13

1 KUDOS received
Intern
Intern
avatar
B
Joined: 16 Feb 2017
Posts: 21

Kudos [?]: 12 [1], given: 72

A certain marathon had 20,000 entrants, 52% of which were female and 3 [#permalink]

Show Tags

New post 25 Aug 2017, 23:53
1
This post received
KUDOS
Bunuel wrote:
A certain marathon had 20,000 entrants, 52% of which were female and 30% of these female entrants were professional runners. If 60% of the entrants were professional, how many of the runners in the marathon were amateur male runners?

A. 72
B. 720
C. 3,120
D. 8,000
E. 8,880


the answer is in attached image.
calculated through the easiest possible method!
hope it helps! :)

Also, lemme know if any explanation is required! 8-)

Attachments

solution.jpg
solution.jpg [ 75.9 KiB | Viewed 371 times ]

Kudos [?]: 12 [1], given: 72

Senior Manager
Senior Manager
avatar
G
Joined: 25 Feb 2013
Posts: 407

Kudos [?]: 173 [0], given: 31

Location: India
GPA: 3.82
GMAT ToolKit User Reviews Badge
Re: A certain marathon had 20,000 entrants, 52% of which were female and 3 [#permalink]

Show Tags

New post 26 Aug 2017, 00:16
Bunuel wrote:
A certain marathon had 20,000 entrants, 52% of which were female and 30% of these female entrants were professional runners. If 60% of the entrants were professional, how many of the runners in the marathon were amateur male runners?

A. 72
B. 720
C. 3,120
D. 8,000
E. 8,880


Another approach - Draw a Tree Structure for these kind of questions

As is clear from the tree structure below -
No of amateur males \(= 0.036*20000 = 720\)

Option B
Attachments

File comment: Tree Structure
Tree structure.jpg
Tree structure.jpg [ 42.65 KiB | Viewed 361 times ]

Kudos [?]: 173 [0], given: 31

Manager
Manager
avatar
B
Joined: 04 May 2014
Posts: 127

Kudos [?]: 9 [0], given: 69

Location: India
WE: Sales (Mutual Funds and Brokerage)
Re: A certain marathon had 20,000 entrants, 52% of which were female and 3 [#permalink]

Show Tags

New post 07 Sep 2017, 21:16
We can use 2X2 Matrix to solve questions of these types
Attachments

Screen Shot 2017-09-08 at 9.45.22 AM.png
Screen Shot 2017-09-08 at 9.45.22 AM.png [ 26.96 KiB | Viewed 199 times ]

Kudos [?]: 9 [0], given: 69

Re: A certain marathon had 20,000 entrants, 52% of which were female and 3   [#permalink] 07 Sep 2017, 21:16
Display posts from previous: Sort by

A certain marathon had 20,000 entrants, 52% of which were female and 3

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


GMAT Club MBA Forum Home| About| Terms and Conditions| 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®.