|
Author |
Message |
|
TAGS:
|
|
|
Senior Manager
Status: ready to boMBArd
Joined: 31 Oct 2010
Posts: 493
Location: India
Concentration: Entrepreneurship, Strategy
GMAT 1: 710 Q48 V40
WE: Project Management (Manufacturing)
Followers: 10
Kudos [?]:
31
[0], given: 67
|
At a certain hospital, 75% of the interns receive fewer than [#permalink]
 03 Feb 2011, 09:23
Question Stats:
58% (02:00) correct
41% (02:22) wrong based on 5 sessions
At a certain hospital, 75% of the interns receive fewer than 6 hours of sleep and report feeling tired during their shifts. At the same time, 70% of the interns who receive 6 or more hours of sleep report no feelings of tiredness. If 80% of the interns receive fewer than 6 hours of sleep, what percent of the interns report no feelings of tiredness during their shifts? A. 6 B. 14 C. 19 D. 20 E. 81
_________________
My GMAT debrief: from-620-to-710-my-gmat-journey-114437.html
|
|
|
|
|
|
|
GMAT Club team member
Joined: 02 Sep 2009
Posts: 11518
Followers: 1792
Kudos [?]:
9538
[3] , given: 826
|
3
This post received
KUDOS
gmatpapa wrote: At a certain hospital, 75% of the interns receive fewer than 6 hours of sleep and report feeling tired during their shifts. At the same time, 70% of the interns who receive 6 or more hours of sleep report no feelings of tiredness. If 80% of the interns receive fewer than 6 hours of sleep, what percent of the interns report no feelings of tiredness during their shifts?
A. 6
B. 14
C. 19
D. 20
E. 81 Given:
| < 6 hours sleep | >= 6 hours sleep | TOTAL |
| Tired | 75 | - | - |
| Not Tired | - | 0.7*X | ? |
| TOTAL | 80 | X | 100 |
Interns who receive < than 6 hours sleep and Not Tired = 80 - 75 = 5; TOTAL interns who receive >= 6 hours sleep = 100 - 80 = 20, so interns who receive >= 6 hours sleep and are Not Tired = 0.7 * 20 =14; Interns who are Not Tired = 5 + 14 = 19. Answer: C.
_________________
PLEASE READ AND FOLLOW: 11 Rules for Posting!!!
RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory
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. NEW!!!
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. NEW!!!
What are GMAT Club Tests?
25 extra-hard Quant Tests
Find out what's new at GMAT Club - latest features and updates
|
|
|
|
|
|
Senior Manager
Status: ready to boMBArd
Joined: 31 Oct 2010
Posts: 493
Location: India
Concentration: Entrepreneurship, Strategy
GMAT 1: 710 Q48 V40
WE: Project Management (Manufacturing)
Followers: 10
Kudos [?]:
31
[0], given: 67
|
Bunuel wrote: gmatpapa wrote: At a certain hospital, 75% of the interns receive fewer than 6 hours of sleep and report feeling tired during their shifts. At the same time, 70% of the interns who receive 6 or more hours of sleep report no feelings of tiredness. If 80% of the interns receive fewer than 6 hours of sleep, what percent of the interns report no feelings of tiredness during their shifts?
A. 6
B. 14
C. 19
D. 20
E. 81 Given:
| < 6 hours sleep | >= 6 hours sleep | TOTAL |
| Tired | 75 | - | - |
| Not Tired | - | 0.7*X | ? |
| TOTAL | 80 | X | 100 |
Interns who receive < than 6 hours sleep and Not Tired = 80 - 75 = 5; TOTAL interns who receive >= 6 hours sleep = 100 - 80 = 20, so interns who receive >= 6 hours sleep and are Not Tired = 0.7 * 20 =14; Interns who are Not Tired = 5 + 14 = 19. Answer: C. Thanks! Bunuel, this tabular method for solving Venn Diagram problems: is it explained anywhere with other examples?
_________________
My GMAT debrief: from-620-to-710-my-gmat-journey-114437.html
|
|
|
|
|
|
GMAT Club team member
Joined: 02 Sep 2009
Posts: 11518
Followers: 1792
Kudos [?]:
9538
[2] , given: 826
|
2
This post received
KUDOS
|
|
|
|
|
|
Senior Manager
Status: ready to boMBArd
Joined: 31 Oct 2010
Posts: 493
Location: India
Concentration: Entrepreneurship, Strategy
GMAT 1: 710 Q48 V40
WE: Project Management (Manufacturing)
Followers: 10
Kudos [?]:
31
[0], given: 67
|
Very useful! Thanks
_________________
My GMAT debrief: from-620-to-710-my-gmat-journey-114437.html
|
|
|
|
|
|
Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 3105
Location: Pune, India
Followers: 567
Kudos [?]:
1997
[0], given: 92
|
Re: Sets problem - Tired [#permalink]
25 Jul 2011, 21:38
vatsas wrote: At a certain hospital, 75% of the interns receive fewer than 6 hours of sleep and report feeling tired during their shifts. At the same time, 70% of the interns who receive 6 or more hours of sleep report no feelings of tiredness. If 80% of the interns receive fewer than 6 hours of sleep, what percent of the interns report no feelings of tiredness during their shifts?
a. 6
b. 14
c. 19
d. 20
e. 81
I need to understand the method to solve this problem. I tried the matrix method but failed. Is there any other method?
Thanks
Sumeet You can just use logic or a Venn diagram, whatever works for you. I will give the logical solution below. Try to figure out the Venn diagram for it. Get back if it gets tricky. Look at the given data line by line. At a certain hospital, 75% of the interns receive fewer than 6 hours of sleep and report feeling tired during their shifts.n(FEW and TIRED) = 75% At the same time, 70% of the interns who receive 6 or more hours of sleep report no feelings of tiredness. .... We will come back... If 80% of the interns receive fewer than 6 hours of sleep, n(FEW) = 80% Therefore, n(Not FEW) = 20% Also since n(FEW and TIRED) = 75%, n(FEW and Not TIRED) = 5% Now we go back to the second sentence. We know that n(Not FEW) = 20%. 70% of these are not tired. So n(Not TIRED and Not FEW) = 70% of 20% = 14% what percent of the interns report no feelings of tiredness during their shifts? n(Not TIRED) = n(FEW and Not TIRED) + n(Not TIRED and Not FEW) = 5% + 14% = 19% The notation is used only to explain it to you. You obviously don't need to do that. Just remember that when you get some data '80% people get less sleep,' it also implies that 20% get enough or more.
_________________
Karishma
Veritas Prep | GMAT Instructor
My Blog
Save 10% on Veritas Prep GMAT Courses And Admissions Consulting
Enroll now. Pay later. Take advantage of Veritas Prep's flexible payment plan options.
Veritas Prep Reviews
|
|
|
|
|
|
Senior Manager
Joined: 24 Mar 2011
Posts: 479
Location: Texas
Followers: 4
Kudos [?]:
33
[1] , given: 20
|
Re: Sets problem - Tired [#permalink]
25 Jul 2011, 22:11
1
This post received
KUDOS
the solution is in the table -
Attachments
table.JPG [ 8 KiB | Viewed 1296 times ]
|
|
|
|
|
|
Intern
Joined: 11 Sep 2011
Posts: 28
Followers: 1
Kudos [?]:
1
[0], given: 0
|
Re: At a certain hospital, 75% of the interns receive fewer than [#permalink]
01 Apr 2012, 00:41
Let's assume total number of students are 1000.
80% of 1000 students gets <6 hrs of sleep = 800 (both tired and not tired)
75% of 1000 students gets <6 hrs and tired = 750
Therefore, students who get <6 hrs and not tired = 50..........(1)
20% of 1000 students gets >= 6 hrs of sleep = 200 (both tired and not tired)
70% of 200 students gets >=6 and not tired = 140.......(2)
(1) + (2) = 190 or 19% of total students. Hence C.
|
|
|
|
|
|
Manager
Joined: 27 Oct 2011
Posts: 196
Location: United States
Concentration: Finance, Strategy
GMAT 1: Q V
GPA: 3.7
WE: Account Management (Consumer Products)
Followers: 1
Kudos [?]:
25
[0], given: 4
|
At a certain hospital, 75% of the interns receive fewer than [#permalink]
15 Apr 2012, 15:31
option c. we figure out at that 20% get more than 6 hours of sleep. then from there we know that 70% of those who get more than 6 hrs of sleep feel tired which is 14% + 5% = 19% 5% = 80-75
_________________
DETERMINED TO BREAK 700!!!
|
|
|
|
|
|
Senior Manager
Joined: 30 Jun 2011
Posts: 272
Followers: 0
Kudos [?]:
10
[0], given: 20
|
Re: At a certain hospital, 75% of the interns receive fewer than [#permalink]
17 Apr 2012, 06:54
Thanks Bunuel for the link to the video
|
|
|
|
|
|
Intern
Joined: 24 Oct 2011
Posts: 2
GMAT Date: 07-27-2012
Followers: 1
Kudos [?]:
0
[0], given: 2
|
At a certain hospital, 75% of the interns receive fewer [#permalink]
21 Jun 2012, 18:53
5% of 80 =4 but why you guys took it as 5% am I mistaking something  hogann wrote: asterixmatrix wrote: 80% receive less than 6 hours of sleep
75% report feeling tired so 5% dont feel tired
20% receive 6 or more hours of sleep
out of this 70% report no tiredness so it become 14%
total 5%+14% = 19%...C Great Explanation - OA is 19% |
|
|
|
|
|
Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 3105
Location: Pune, India
Followers: 567
Kudos [?]:
1997
[0], given: 92
|
Re: Tuesday Q2 - Interns [#permalink]
21 Jun 2012, 21:58
RichaMidha2012 wrote: 5% of 80 =4 but why you guys took it as 5% am I mistaking something asterixmatrix wrote: 80% receive less than 6 hours of sleep
75% report feeling tired so 5% dont feel tired
20% receive 6 or more hours of sleep
out of this 70% report no tiredness so it become 14%
total 5%+14% = 19%...C A very important thing in percentages is to note what is the % of i.e. when I say 5%, it is 5% of what? 5% of total interns or 5% of interns who receive less than 6 hrs of sleep or 5% of interns who report tiredness etc The question says: 75% of the interns receive fewer than 6 hours of sleep and report feeling tired during their shifts (75% of total interns) If 80% of the interns receive fewer than 6 hours of sleep (again, 80% of the total interns) So out of 80% of total interns i.e. if total interns are 100, 80 of them receive fewer than 6 hrs of sleep. Out of 100, 75 receive fewer than 6 hrs of sleep and report tiredness. Therefore, 5 receive fewer than 6 hrs of sleep but report no tiredness.
_________________
Karishma
Veritas Prep | GMAT Instructor
My Blog
Save 10% on Veritas Prep GMAT Courses And Admissions Consulting
Enroll now. Pay later. Take advantage of Veritas Prep's flexible payment plan options.
Veritas Prep Reviews
|
|
|
|
|
|
Director
Joined: 02 Jul 2012
Posts: 753
Location: India
Concentration: Strategy
GMAT 1: 740 Q49 V42
GPA: 3.8
WE: Engineering (Energy and Utilities)
Followers: 19
Kudos [?]:
255
[0], given: 45
|
AartiPajan wrote: At a certain hospital, 75% of the interns receive fewer than 6 hours of sleep and report feeling tired during their shifts. At the same time, 70% of interns who receive 6 hours or more of sleep report no feeling of tiredness. If 80% of the interns receive fewer than 6 hrs sleep, what percentage of interns report no feelings of tiredness during their shift?
A. 6
B. 14
C. 19
D. 20
E. 81
Plz help... My solution says D. 20 while correct answer is C. 19 ..
Thanks in advance. Creating a two overlapping set grid ____________Less Than 6________6 or more__________________Total Tired__________75________________6______________________81 Not Tired________5_______________14______________________19 Total__________80_______________20_____________________100 Kudos Please... If my post helped.
_________________
Kudos Please... If my post helped.
Thanks To The Almighty - My GMAT Debrief
My Own CR Question 1|My Own CR Question 2|My Own DS Question 1|My Own DS Question 2|
My Own PS Question 1
|
|
|
|
|
|
Intern
Joined: 28 Aug 2012
Posts: 47
Concentration: Operations, Marketing
GMAT 1: 510 Q36 V25
GPA: 4
WE: Information Technology (Other)
Followers: 0
Kudos [?]:
23
[0], given: 99
|
Re: At a certain hospital, 75% of the interns receive fewer than [#permalink]
16 Feb 2013, 12:00
Guys, I am like SUPER CONFUSED right now  .. I used the tabular method to solve the problem but it was just the opposite to the explanations (ie). Tired and not tired in the X axis, Receive < 6 hrs , >6 hours in the Y axis .. I know this would yield the same answer but im confused.. If someone could explain by drawing the grid the way i did.. id be really really grateful. And also, how do u choose which attribute to go where.. does that really matter?? Thanks in advance
|
|
|
|
|
|
Manager
Status: Fondling the GMAT
Joined: 22 Feb 2012
Posts: 175
Location: India
Concentration: Finance, International Business
GMAT Date: 06-20-2013
GPA: 2.34
WE: Business Development (Manufacturing)
Followers: 14
Kudos [?]:
88
[1] , given: 67
|
Re: At a certain hospital, 75% of the interns receive fewer than [#permalink]
16 Feb 2013, 12:39
1
This post received
KUDOS
thinktank wrote: Guys, I am like SUPER CONFUSED right now .. I used the tabular method to solve the problem but it was just the opposite to the explanations (ie). Tired and not tired in the X axis, Receive < 6 hrs , >6 hours in the Y axis .. I know this would yield the same answer but im confused.. If someone could explain by drawing the grid the way i did.. id be really really grateful. And also, how do u choose which attribute to go where.. does that really matter?? Thanks in advance for explanation, Pls go thru the attachment. see if it makes sense. Regards, Abhijit
Attachments
 Book1.xlsx [10.95 KiB]
Downloaded 12 times
_________________
Please Read this before Posting your question rules-for-posting-in-verbal-gmat-forum-134642.html#p1097623
When it rains, All birds occupy shelters. But Eagle is the only bird that avoids the rain by flying above the clouds.
Problems common to all. Attitude makes the difference
Concept Initiator Articles
co-ordinate-geometry-simplified-149570.html
time-speed-and-distance-simplified-150163.html
permutations-and-combinations-simplified-150835.html
UPCOMING in Simplification Series - Probability Simplified.
|
|
|
|
|
|
Intern
Joined: 28 Aug 2012
Posts: 47
Concentration: Operations, Marketing
GMAT 1: 510 Q36 V25
GPA: 4
WE: Information Technology (Other)
Followers: 0
Kudos [?]:
23
[0], given: 99
|
Re: At a certain hospital, 75% of the interns receive fewer than [#permalink]
17 Feb 2013, 21:28
Narenn wrote: thinktank wrote: Guys, I am like SUPER CONFUSED right now .. I used the tabular method to solve the problem but it was just the opposite to the explanations (ie). Tired and not tired in the X axis, Receive < 6 hrs , >6 hours in the Y axis .. I know this would yield the same answer but im confused.. If someone could explain by drawing the grid the way i did.. id be really really grateful. And also, how do u choose which attribute to go where.. does that really matter?? Thanks in advance for explanation, Pls go thru the attachment. see if it makes sense. Regards, Abhijit Abhijit ! Thank you so much for the effort u ve put in.  +1 to u
|
|
|
|
|
|
Senior Manager
Joined: 13 Aug 2012
Posts: 468
Followers: 12
Kudos [?]:
74
[0], given: 11
|
Re: At a certain hospital, 75% of the interns receive fewer than [#permalink]
03 Mar 2013, 21:26
-------------Fewer than 6 / 6 or more
--not tired-- .75x.
--tired------ .05x. /------.14x-------/---.19x----
Total-----------.80x-------/------.20x-------/---x-------
Answer: C
|
|
|
|
|
|
Intern
Joined: 23 Feb 2013
Posts: 1
Followers: 0
Kudos [?]:
0
[0], given: 1
|
Re: Sets problem - Tired [#permalink]
07 Apr 2013, 17:19
agdimple333 wrote: the solution is in the table - I'm trying to understand why you had to calculate "70% of 20" but at the same time you left "5" untouched? Why would we take % of a %?
|
|
|
|
|
|
GMAT Club team member
Joined: 02 Sep 2009
Posts: 11518
Followers: 1792
Kudos [?]:
9538
[0], given: 826
|
Re: Sets problem - Tired [#permalink]
07 Apr 2013, 22:45
|
|
|
|
|
|
|
Re: Sets problem - Tired
[#permalink]
07 Apr 2013, 22:45
|
|
|
|
|
|
|
|
|
Similar topics |
Author |
Replies |
Last post |
|
Similar
Topics:
|
 |
|
|
At a certain hospital, 75% of the interns receive fewer than
|
empty_spaces |
2 |
25 Aug 2007, 22:01 |
|
|
|
|
At a certain hospital, 75% of the interns receive fewer than
|
pinal2 |
8 |
25 Dec 2007, 22:01 |
|
|
|
|
At a certain hospital, 75% of the interns receive fewer than
|
chineseburned |
1 |
22 Mar 2008, 18:18 |
|
|
|
|
At a certain hospital, 75% of the interns receive fewer than
|
agold |
3 |
24 Mar 2008, 16:37 |
|
|
1
|
|
At a certain hospital, 75% of the interns receive fewer than
|
dancinggeometry |
6 |
22 Sep 2008, 02:09 |
|
|
|
|
|
|
close
