Events & Promotions
|
|
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Apr 2610:00 AM EDT
-11:00 AM EDT
The Target Test Prep course represents a quantum leap forward in GMAT preparation, a radical reinterpretation of the way that students should study. Try before you buy with a 5-day, full-access trial of the course for FREE!
Apr 2711:00 AM EDT
-12:00 PM EDT
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors
Apr 2808:00 AM PDT
-11:00 AM PDT
Whether you are just beginning your MBA journey or fine-tuning your path to a 700+ score, GMAT Day is designed to give you a competitive edge.
E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
15%
(low)
Question Stats:
80% (00:56) correct
20%
(01:02)
wrong
based on 540
sessions
History
Date
Time
Result
Not Attempted Yet
Attachment:
Bookrack.PNG [ 4.5 KiB | Viewed 28501 times ]
(1) x = 50 centimeters.
(2) Twelve of the volumes have an average (arithmetic mean) thickness of 5 centimeters.
Hi please go through the attached file for the problem from gmat prep -
is it not a given that all the volumes of the book are of the same thickness so once you know
sum of the thickness of 12 volumes = given average x 12 = 60
then you can find the individual thickness = 5 !!
my answer was c
I find this strange at time - gmat assumes what it wants to but does not allow us to assume the obvious !
is it not a given that all the volumes of the book are of the same thickness so once you know
sum of the thickness of 12 volumes = given average x 12 = 60
then you can find the individual thickness = 5 !!
my answer was c
I find this strange at time - gmat assumes what it wants to but does not allow us to assume the obvious !
26 Feb 2012, 04:25
Kudos
Bookmarks
Will the first 10 volumes of a 20-volume encyclopedia fit upright in the bookrack shown above?
(1) x = 50 centimeters. Clearly insufficient.
(2) Twelve of the volumes have an average (arithmetic mean) thickness of 5 centimeters. You most certainly can not assume that thickness of each of the 20 volumes is 5 centimeters, moreover you can not even assume that thickness of each of theses 12 volumes is 5 centimeters. Yes, the total thickness of these 12 volumes is 12*5=60 centimeters, but individual thicknesses could be {1, 1, 1, ..., 1, 49} or {2, 2, 2, ..., 2, 38} ... Next, you don't know which 12 volumes have an average thickness of 5 centimeters: first 12? last 12? first 6 and last 6? So, this statement is not sufficient.
(1)+(2) It's certainly possible that all 20 volumes to have thicknesses of 5 centimeters and in this case the first 10 volumes will fit in the bookrack of 50 centimeters but it's also possible that the last 12 volumes to have an average thickness of 5 centimeters and the first 8 volumes have thicknesses of 100 meters each (why not?) and in this case the first 10 volumes will NOT fit in the bookrack of 50 centimeters. Not sufficient.
Answer: E.
Hope it's clear.
(1) x = 50 centimeters. Clearly insufficient.
(2) Twelve of the volumes have an average (arithmetic mean) thickness of 5 centimeters. You most certainly can not assume that thickness of each of the 20 volumes is 5 centimeters, moreover you can not even assume that thickness of each of theses 12 volumes is 5 centimeters. Yes, the total thickness of these 12 volumes is 12*5=60 centimeters, but individual thicknesses could be {1, 1, 1, ..., 1, 49} or {2, 2, 2, ..., 2, 38} ... Next, you don't know which 12 volumes have an average thickness of 5 centimeters: first 12? last 12? first 6 and last 6? So, this statement is not sufficient.
(1)+(2) It's certainly possible that all 20 volumes to have thicknesses of 5 centimeters and in this case the first 10 volumes will fit in the bookrack of 50 centimeters but it's also possible that the last 12 volumes to have an average thickness of 5 centimeters and the first 8 volumes have thicknesses of 100 meters each (why not?) and in this case the first 10 volumes will NOT fit in the bookrack of 50 centimeters. Not sufficient.
Answer: E.
Hope it's clear.
General Discussion
14 Jun 2019, 05:18
Kudos
Bookmarks
morya003
Target question: Will the first 10 volumes of a 20-volume encyclopedia fit upright in the bookrack shown above?
Statement 1: x = 50 centimeters.
We have no idea how THICK the first 10 volumes are.
They COULD each be 1 mm thick, in which case the 10 volumes will easily fit in the 50 cm rack
Or they COULD each be 1 km thick, in which case the 10 volumes will NOT fit in the 50 cm rack
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: Twelve of the volumes have an average (arithmetic mean) thickness of 5 centimeters.
We have no idea how wide the book rack is.
Statement 2 is NOT SUFFICIENT
Statements 1 and 2 combined
We have no info about the thickness of the 10 volumes to be placed in the rack.
Consider these two possible cases:
Case a: Each of the 12 volumes noted above in statement 2 are 5 cm thick. Two of those 5-cm-thick volumes are added to eight volumes that are each 1 mm thick. In this case, the 10 volumes will easily fit in the 50 cm rack
Case b: Each of the 12 volumes noted above in statement 2 are 5 cm thick. Two of those 5-cm-thick volumes are added to eight volumes that are each 1 km thick. In this case, the 10 volumes will NOT fit in the 50 cm rack
Since we cannot answer the target question with certainty, the combined statements are NOT SUFFICIENT
Answer: E
Cheers,
Brent
