Will the first 10 volumes of a 20-volume encyclopedia fit : GMAT Data Sufficiency (DS)
Check GMAT Club App Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 09 Dec 2016, 12:24

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# Will the first 10 volumes of a 20-volume encyclopedia fit

Author Message
TAGS:

### Hide Tags

Manager
Joined: 25 Dec 2011
Posts: 54
GMAT Date: 05-31-2012
Followers: 0

Kudos [?]: 39 [1] , given: 29

Will the first 10 volumes of a 20-volume encyclopedia fit [#permalink]

### Show Tags

26 Feb 2012, 02:55
1
KUDOS
1
This post was
BOOKMARKED
00:00

Difficulty:

5% (low)

Question Stats:

78% (01:22) correct 22% (00:03) wrong based on 98 sessions

### HideShow timer Statistics

Attachment:

Bookrack.PNG [ 4.5 KiB | Viewed 4771 times ]
Will the first 10 volumes of a 20-volume encyclopedia fit upright in the bookrack shown above?

(1) x = 50 centimeters.
(2) Twelve of the volumes have an average (arithmetic mean) thickness of 5 centimeters.

[Reveal] Spoiler:
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 !!

I find this strange at time - gmat assumes what it wants to but does not allow us to assume the obvious !
[Reveal] Spoiler: OA

Last edited by Bunuel on 26 May 2013, 04:21, edited 3 times in total.
Edited the question and added the figure
Math Expert
Joined: 02 Sep 2009
Posts: 35932
Followers: 6860

Kudos [?]: 90090 [3] , given: 10413

Re: Will the first 10 volumes of a 20-volume encyclopedia fit [#permalink]

### Show Tags

26 Feb 2012, 03:25
3
KUDOS
Expert's post
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.

Hope it's clear.
_________________
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 12904
Followers: 562

Kudos [?]: 158 [0], given: 0

Re: Will the first 10 volumes of a 20-volume encyclopedia fit [#permalink]

### Show Tags

22 Feb 2015, 07:13
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 Legend
Joined: 09 Sep 2013
Posts: 12904
Followers: 562

Kudos [?]: 158 [0], given: 0

Re: Will the first 10 volumes of a 20-volume encyclopedia fit [#permalink]

### Show Tags

01 Mar 2016, 07:08
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.
_________________
Re: Will the first 10 volumes of a 20-volume encyclopedia fit   [#permalink] 01 Mar 2016, 07:08
Similar topics Replies Last post
Similar
Topics:
An online grocery delivers groceries for $10.00 for the first box of f 2 08 Dec 2015, 08:30 An online grocery delivers groceries for$10.00 for the first box of f 3 26 Jun 2015, 01:58
3 A sales associate earns a commission of 8% on her first \$10, 4 15 Jul 2014, 23:04
1 A certain encyclopedia has 20 volumes, each of which is w 5 06 Aug 2011, 04:08
6 What is the volume of the cube above? 9 26 Oct 2010, 08:07
Display posts from previous: Sort by