Find all School-related info fast with the new School-Specific MBA Forum

It is currently 01 Aug 2015, 02:57
GMAT Club 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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

A probably medium question, pls help to explain the middle.

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Manager
Manager
avatar
Status: Single
Joined: 05 Jun 2011
Posts: 130
Location: Shanghai China
Followers: 2

Kudos [?]: 11 [0], given: 0

A probably medium question, pls help to explain the middle. [#permalink] New post 24 Jul 2011, 02:45
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

40% (02:21) correct 60% (00:21) wrong based on 5 sessions
In Township K, 1/5 of the housing units are equiped with cable Tv. If 1/10 of the housing units, including 1/3 of those that are equiped with cable tv, are equipped with videocassette recorders, what fraction of the housing units have neither cable tv nor videocassette recorders?

a)23/30
b)11/15
c)7/10
d)1/6
e)2/15

I calculate at the middle that 1/10*1/3= 1/30. but the answer is 1/15, why is that? I made the mistake at this point, pls instruct me. thank u~
[Reveal] Spoiler: OA
Manager
Manager
avatar
Joined: 31 May 2011
Posts: 88
Location: India
Concentration: Finance, International Business
GMAT Date: 12-07-2011
GPA: 3.22
WE: Information Technology (Computer Software)
Followers: 1

Kudos [?]: 38 [0], given: 4

Re: A probably medium question, pls help to explain the middle. [#permalink] New post 24 Jul 2011, 05:12
tracyyahoo wrote:
In Township K, 1/5 of the housing units are equiped with cable Tv. If 1/10 of the housing units, including 1/3 of those that are equiped with cable tv, are equipped with videocassette recorders, what fraction of the housing units have neither cable tv nor videocassette recorders?

a)23/30
b)11/15
c)7/10
d)1/6
e)2/15

I calculate at the middle that 1/10*1/3= 1/30. but the answer is 1/15, why is that? I made the mistake at this point, pls instruct me. thank u~


1/5 -- cable TV (This includes some data from video cassette recorder)
1/10 -- video cassette recorder including 1/3(equiped with cable tv) i.e. 1/3(1/5) = 1/15

therefore only video cassette recorder = 1/10 - 1/15 = 1/30
Total = 1/5+1/30+neither cable tv nor videocassette recorders
1 = 7/30 + neither cable tv nor videocassette recorders
therefore neither cable tv nor videocassette recorders = 1-7/30 = 23/30

Hence A.
Re: A probably medium question, pls help to explain the middle.   [#permalink] 24 Jul 2011, 05:12
    Similar topics Author Replies Last post
Similar
Topics:
A Medium question, pls help me to explain tracyyahoo 5 24 Jul 2011, 02:31
1 Probability - Can someone pls help me with this ques.. DeeptiM 4 23 Jul 2011, 23:36
Someone Help Explain This to Me - Probability shs0145 4 21 Jun 2011, 07:53
Pls help (Probability w. dice) test800 3 07 Jun 2010, 05:46
2 Experts publish their posts in the topic Help with an easy probability question changhiskhan 4 18 Mar 2010, 22:56
Display posts from previous: Sort by

A probably medium question, pls help to explain the middle.

  Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Privacy Policy| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group and phpBB SEO

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®.