NEW HERE? LEARN MORE
closeclose
Last visit was: 25 Apr 2024, 14:56 It is currently 25 Apr 2024, 14:56
Decision Tracker
My Rewards
New posts
New comers' posts

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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel

The ratio of boys to girls in a class is 3 to 5. If 2 boys are added t

SORT BY:
Date
Kudos
Tags:
Find Similar Topics 
Show Tags
Hide Tags
avatar
L
TheUltimateWinner
CEO
CEO
Joined: 23 Feb 2015
Posts: 2519
Own Kudos [?]: 2096 [7]
Given Kudos: 1976
Concentration: Finance, Technology
Schools: Harvard '24 Judge '23 LBS '24 McCombs '24 Mendoza Tepper '24 Ross '24 Cox Marshall '24 Fisher Kelley '24 Jones McDonough '24 Owen '24 Terry BU Simon '24 Katz GWU Mason Babson Gabelli Foster '24 Goizueta '24 Scheller Stern '23 CBS '23 Booth '23 Haas '25 Wharton '25 Stanford '26 Johnson'23 Fuqua '23 Kellogg '23 Kenan-Flagler'23 INSEAD Aug 22 intake Olin '23 Said '23 Sloan '23 Carey Arizona "22 Yale '23 UC Davis Madison '23 Anderson '23 Carroll Carlson '23 Darden '23
Send PM
GMAT ToolKit User CAT Tests
The ratio of boys to girls in a class is 3 to 5. If 2 boys are added t [#permalink] New post   10 May 2020, 08:31
7
Bookmarks
00:00
A
B
C
D
E

Difficulty:

5% (low)

Question Stats:

91% (01:45) correct 9% (02:33) wrong based on 114 sessions
Hide Show timer Statistics
The ratio of boys to girls in a class is 3 to 5. If 2 boys are added to the class and 6 girls leave the class, the new ratio of boys to girls is 5 to 6. How many girls were in the class to begin with?
A) 15
B) 20
C) 25
D) 30
E) 35
ShowHide Answer
Official Answer
D
User avatar
L
GMATinsight
GMAT Club Legend
GMAT Club Legend
Joined: 08 Jul 2010
Status:GMAT/GRE Tutor l Admission Consultant l On-Demand Course creator
Posts: 5960
Own Kudos [?]: 13387 [0]
Given Kudos: 124
Location: India
GMAT: QUANT+DI EXPERT
Schools: IIM (A) ISB '24
GMAT 1: 750 Q51 V41
WE:Education (Education)
Send PM
Reviews Badge
The ratio of boys to girls in a class is 3 to 5. If 2 boys are added t [#permalink] New post   Updated on: 10 May 2020, 08:50
Expert Reply
Asad wrote:
The ratio of boys to girls in a class is 3 to 5. If 2 boys are added to the class and 6 girls leave the class, the new ratio of boys to girls is 5 to 6. How many girls were in the class to begin with?
A) 15
B) 20
C) 25
D) 30
E) 35


Boys = 3x
Girls = 5x

(3x+2):(5x-6) = 5:6

i.e. 18x+12 = 25x-30

i.e. 7x = 42

i.e. x = 6

Girls in beginning = 5x = 30

Answer: Option D

Originally posted by GMATinsight on 10 May 2020, 08:34.
Last edited by GMATinsight on 10 May 2020, 08:50, edited 1 time in total.
User avatar
L
Archit3110
GMAT Club Legend
GMAT Club Legend
Joined: 18 Aug 2017
Status:You learn more from failure than from success.
Posts: 8019
Own Kudos [?]: 4097 [1]
Given Kudos: 242
Location: India
Concentration: Sustainability, Marketing
GMAT Focus 1:
545 Q79 V79 DI73
GPA: 4
WE:Marketing (Energy and Utilities)
Send PM
GMAT ToolKit User CAT Tests
Re: The ratio of boys to girls in a class is 3 to 5. If 2 boys are added t [#permalink] New post   10 May 2020, 08:47
1
Kudos
GMATinsight ; see highlighted part

GMATinsight wrote:
Asad wrote:
The ratio of boys to girls in a class is 3 to 5. If 2 boys are added to the class and 6 girls leave the class, the new ratio of boys to girls is 5 to 6. How many girls were in the class to begin with?
A) 15
B) 20
C) 25
D) 30
E) 35


Boys = 3x
Girls = 5x

(3x+2):(5x-6) = 5:6

i.e. 18x+12 = 25x-30

i.e. 7x = 42

i.e. [highlight]x = 7[/highlight]

Girls in beginning = 5x = 35

Answer: Option E
User avatar
L
Archit3110
GMAT Club Legend
GMAT Club Legend
Joined: 18 Aug 2017
Status:You learn more from failure than from success.
Posts: 8019
Own Kudos [?]: 4097 [0]
Given Kudos: 242
Location: India
Concentration: Sustainability, Marketing
GMAT Focus 1:
545 Q79 V79 DI73
GPA: 4
WE:Marketing (Energy and Utilities)
Send PM
GMAT ToolKit User CAT Tests
The ratio of boys to girls in a class is 3 to 5. If 2 boys are added t [#permalink] New post   10 May 2020, 08:49
Asad wrote:
The ratio of boys to girls in a class is 3 to 5. If 2 boys are added to the class and 6 girls leave the class, the new ratio of boys to girls is 5 to 6. How many girls were in the class to begin with?
A) 15
B) 20
C) 25
D) 30
E) 35



given
boys/girls = 3/5
b= 3g/5
also
b+2/g-6 = 5/6
6b+12 = 5g-30
solve for g
18g/5-5g = -42
18g-25g = -42 *5
-7g = -42*5
g= 30

OPTION D
User avatar
L
Abhishek009
Board of Directors
Joined: 11 Jun 2011
Status:QA & VA Forum Moderator
Posts: 6072
Own Kudos [?]: 4689 [0]
Given Kudos: 463
Location: India
GPA: 3.5
WE:Business Development (Commercial Banking)
Send PM
GMAT ToolKit User
Re: The ratio of boys to girls in a class is 3 to 5. If 2 boys are added t [#permalink] New post   10 May 2020, 08:54
Asad wrote:
The ratio of boys to girls in a class is 3 to 5. If 2 boys are added to the class and 6 girls leave the class, the new ratio of boys to girls is 5 to 6. How many girls were in the class to begin with?
A) 15
B) 20
C) 25
D) 30
E) 35


\(\frac{b}{g} = \frac{3x}{5x}\)

\(\frac{b + 2}{g - 6 } = \frac{3x + 2}{5x - 6 } = \frac{5}{6}\)

Now, \(18x + 12 = 25x - 30\)

Or, \(7x = 42\)

So, \(x = 6\) , So Number of girls in the beginng is 5*6 = 30, Annswer must be (D) 30
User avatar
bumpbot
Non-Human User
Joined: 09 Sep 2013
Posts: 32679
Own Kudos [?]: 822 [0]
Given Kudos: 0
Send PM
Re: The ratio of boys to girls in a class is 3 to 5. If 2 boys are added t [#permalink] New post   01 Jun 2023, 22:20
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 Club Bot
gmatclubot
Re: The ratio of boys to girls in a class is 3 to 5. If 2 boys are added t [#permalink]
01 Jun 2023, 22:20
Moderators:
Bunuel
Math Expert
92915 posts
yashikaaggarwal
Senior Moderator - Masters Forum
3137 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions