It is currently 09 Dec 2018, 11:37
My Tests

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.

A class consists of 12 girls and 20 boys. One quarter of the

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 07 Jun 2014
Posts: 4749
GRE 1: Q167 V156
WE: Business Development (Energy and Utilities)
Followers: 93

Kudos [?]: 1650 [0], given: 396

CAT Tests
A class consists of 12 girls and 20 boys. One quarter of the [#permalink] New post 30 Jul 2018, 10:54
Expert's post
00:00

Question Stats:

68% (00:35) correct 31% (01:18) wrong based on 19 sessions
A class consists of 12 girls and 20 boys. One quarter of the girls in the class have blue eyes. If a child is selected at random from the class, what is the probability that the child is a girl who does not have blue eyes?

(A) \(\frac{3}{32}\)
(B) \(\frac{9}{32}\)
(C) \(\frac{3}{8}\)
(D) \(\frac{23}{32}\)
(E) \(\frac{29}{32}\)
[Reveal] Spoiler: OA

_________________

Sandy
If you found this post useful, please let me know by pressing the Kudos Button

Try our free Online GRE Test

Manager
Manager
Joined: 06 Jun 2018
Posts: 94
Followers: 0

Kudos [?]: 56 [0], given: 0

Re: A class consists of 12 girls and 20 boys. One quarter of the [#permalink] New post 31 Jul 2018, 03:01
sandy wrote:
A class consists of 12 girls and 20 boys. One quarter of the girls in the class have blue eyes. If a child is selected at random from the class, what is the probability that the child is a girl who does not have blue eyes?

(A) \(\frac{3}{32}\)
(B) \(\frac{9}{32}\)
(C) \(\frac{3}{8}\)
(D) \(\frac{23}{32}\)
(E) \(\frac{29}{32}\)



Total : 12 + 20 = 32

Girls who have blue eyes = 12*1/4 = 3

Girls who don't have blue eyes = 9

Probability = 9/32

The best answer is B.
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 07 Jun 2014
Posts: 4749
GRE 1: Q167 V156
WE: Business Development (Energy and Utilities)
Followers: 93

Kudos [?]: 1650 [0], given: 396

CAT Tests
Re: A class consists of 12 girls and 20 boys. One quarter of the [#permalink] New post 08 Aug 2018, 18:12
Expert's post
Explanation

The probability of any outcome is equal to the number of desired outcomes divided by the total number of outcomes. There are 12 girls and 20 boys in the classroom. If one-quarter of the girls have blue eyes, then there are \((12)\frac{1}{3} = 3\) girls with blue eyes.

Therefore, there are \(12 - 3 = 9\) girls who do not have blue eyes. The total number of ways in which a child could be chosen is the total number of children in the class, namely 12 + 20 = 32. Therefore, the probability of choosing a girl who does not have blue eyes equals the number of girls without blue eyes divided by the total number of children, which is \(\frac{9}{32}\).
_________________

Sandy
If you found this post useful, please let me know by pressing the Kudos Button

Try our free Online GRE Test

Target Test Prep Representative
User avatar
Status: Head GRE Instructor
Affiliations: Target Test Prep
Joined: 09 May 2016
Posts: 161
Location: United States
Followers: 4

Kudos [?]: 117 [0], given: 0

Re: A class consists of 12 girls and 20 boys. One quarter of the [#permalink] New post 10 Aug 2018, 18:11
Expert's post
sandy wrote:
A class consists of 12 girls and 20 boys. One quarter of the girls in the class have blue eyes. If a child is selected at random from the class, what is the probability that the child is a girl who does not have blue eyes?

(A) \(\frac{3}{32}\)
(B) \(\frac{9}{32}\)
(C) \(\frac{3}{8}\)
(D) \(\frac{23}{32}\)
(E) \(\frac{29}{32}\)


Since ¼ of the 12 girls have blue eyes, ¼ x 12 = 3 girls have blue eyes. So 9 girls don’t have blue eyes. Since there are 12 + 20 = 32 students in the class, the probability that a child is a girl who does not have blue eyes is 9/32.

Answer: B
_________________

Jeffery Miller
Head of GRE Instruction

GRE Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Re: A class consists of 12 girls and 20 boys. One quarter of the   [#permalink] 10 Aug 2018, 18:11
Display posts from previous: Sort by

A class consists of 12 girls and 20 boys. One quarter of the

  Question banks Downloads My Bookmarks Reviews Important topics  


GRE Prep Club Forum Home| About| Terms and Conditions and Privacy Policy| GRE Prep Club Rules| Contact

Powered by phpBB © phpBB Group

Kindly note that the GRE® test is a registered trademark of the Educational Testing Service®, and this site has neither been reviewed nor endorsed by ETS®.