It is currently 21 Sep 2017, 16:18

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.

Close

Request Expert Reply

Confirm Cancel

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

If the length of each edge of a certain rectangular solid is an

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

3 KUDOS received
Manager
Manager
User avatar
Joined: 10 Sep 2014
Posts: 72

Kudos [?]: 90 [3], given: 102

If the length of each edge of a certain rectangular solid is an [#permalink]

Show Tags

New post 09 Feb 2015, 03:36
3
This post received
KUDOS
3
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  85% (hard)

Question Stats:

47% (01:18) correct 53% (01:30) wrong based on 101 sessions

HideShow timer Statistics

If the length of each edge of a certain rectangular solid is an integer and exactly four of its faces have the same dimensions, then what is the volume of the rectangular solid?

(1) Two of the faces have areas of 32 square units and 16 square units.

(2) One of the edges is twice the length of another edge.
[Reveal] Spoiler: OA

_________________

Press KUDOs if you find my explanation helpful

Kudos [?]: 90 [3], given: 102

Expert Post
EMPOWERgmat Instructor
User avatar
P
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 9800

Kudos [?]: 3312 [0], given: 171

Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: 340 Q170 V170
Re: If the length of each edge of a certain rectangular solid is an [#permalink]

Show Tags

New post 09 Feb 2015, 12:56
Hi TARGET730,

This DS question has a number of interesting "restrictions" to it (and you have to pay careful attention to the restrictions to get the correct answer).

Here, we have a rectangular solid that has 4 faces with the same dimensions. In real basic terms, we have a box (NOT a cube), with the dimensions X, X and Y. We're also told that each dimension is an INTEGER. We're asked for the VOLUME of the solid.

Volume = (length)(width)(height)

Fact 1: Two of the faces have areas of 32 and 16

Since this rectangular solid has 4 faces with the same dimensions, the other 2 faces will have dimensions that match (but are different from the other 4 faces).

With the above values, we have just 2 possibilities:
The 4 sides are 32s and the 2 sides are 16s
The 4 sides are 16s and the 2 sides are 32s

While many Test Takers might dismiss this as insufficient, we need to do a bit more work to PROVE whether it's sufficient or insufficient.

If the 2 sides are 16s, then the two dimensions are 4 and 4
Since the others sides are 32s, those dimensions are 4 and 8
The volume of this solid is (4)(4)(8) = 126

If the 2 sides are 32s, then the two dimensions are (root32) and (root32).
The prompt stated that the dimensions had to be INTEGERS though, so this set of dimensions does NOT MATCH the restrictions given. Thus, there is only one answer in Fact 1.
Fact 1 is SUFFICIENT

Fact 2: One of the edges is twice the length of another.

We could have (4)(4)(8) =126
We could have (1)(1)(2) = 2
Fact 2 is INSUFFICIENT.

Final Answer:
[Reveal] Spoiler:
A


GMAT assassins aren't born, they're made,
Rich
_________________

760+: Learn What GMAT Assassins Do to Score at the Highest Levels
Contact Rich at: Rich.C@empowergmat.com

Rich Cohen

Co-Founder & GMAT Assassin

Special Offer: Save $75 + GMAT Club Tests Free

Official GMAT Exam Packs + 70 Pt. Improvement Guarantee
www.empowergmat.com/

***********************Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!***********************

Kudos [?]: 3312 [0], given: 171

Manager
Manager
User avatar
Joined: 10 Sep 2014
Posts: 72

Kudos [?]: 90 [0], given: 102

Re: If the length of each edge of a certain rectangular solid is an [#permalink]

Show Tags

New post 16 Feb 2015, 04:46
Hi Rich,
I am not sure the OA is correct. i am trying to find the correct answer answer here. Can we consider the following possibilities with different volumes?

Area 32
------
32 * 1
16 * 2
8 * 4


Area 16
------
1 * 16
2 * 8
4 * 4

Volume
-------
36 * 1 * 16 = 576
16 * 2 * 8 = 196
8 * 4 * 4 = 128
_________________

Press KUDOs if you find my explanation helpful

Kudos [?]: 90 [0], given: 102

Expert Post
EMPOWERgmat Instructor
User avatar
P
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 9800

Kudos [?]: 3312 [0], given: 171

Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: 340 Q170 V170
Re: If the length of each edge of a certain rectangular solid is an [#permalink]

Show Tags

New post 16 Feb 2015, 17:52
Hi TARGET730,

In the description of the rectangular solid, we're told that "4 of the faces have the same dimensions" - the ONLY way for that to occur is if the dimensions of the solid are X, X and Y (2 of the 3 dimensions MUST have the same length). We're also told that ALL the dimensions MUST be INTEGERS.

Using these restrictions, how many of your 'examples' actually match? You'll find that just one "fits" (the 4x4x8), so the final answer is
[Reveal] Spoiler:
C


GAMT assassins aren't born, they're made,
Rich
_________________

760+: Learn What GMAT Assassins Do to Score at the Highest Levels
Contact Rich at: Rich.C@empowergmat.com

Rich Cohen

Co-Founder & GMAT Assassin

Special Offer: Save $75 + GMAT Club Tests Free

Official GMAT Exam Packs + 70 Pt. Improvement Guarantee
www.empowergmat.com/

***********************Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!***********************

Kudos [?]: 3312 [0], given: 171

GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 17587

Kudos [?]: 270 [0], given: 0

Premium Member
Re: If the length of each edge of a certain rectangular solid is an [#permalink]

Show Tags

New post 26 May 2016, 07:44
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 Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Kudos [?]: 270 [0], given: 0

Senior Manager
Senior Manager
User avatar
G
Joined: 29 Jun 2017
Posts: 307

Kudos [?]: 52 [0], given: 61

WE: Engineering (Transportation)
GMAT ToolKit User Reviews Badge
Re: If the length of each edge of a certain rectangular solid is an [#permalink]

Show Tags

New post 05 Sep 2017, 05:46
Ans is A
Length is integer, and 4 faces have equal areas
1) A1=32 and A2=16
from this LxB= 32 and \(B^2 = 16\), \(=> B= 4\) and \(L =8\) and Volume= 8x4x4 = 128 cu.units

or BxL =32 and \(L^2 = 16\), \(=> L=4\) and\(B = 8\) and in this case Volume = 4x4x8 = 128 cu. units

Note B and L cant take any other value as L is an integer mentioned in question.

2) \(L = 2B\) or \(B = 2L\)
Clearly statement is insufficient to answer about volume which is \(L^2\) x B or \(B^2\) x L
_________________

Give Kudos for correct answer and/or if you like the solution.

Kudos [?]: 52 [0], given: 61

Re: If the length of each edge of a certain rectangular solid is an   [#permalink] 05 Sep 2017, 05:46
    Similar topics Author Replies Last post
Similar
Topics:
6 EXPERTS_POSTS_IN_THIS_TOPIC The length of a rectangular solid is a, its width is b, and eladshush 8 15 Mar 2017, 01:48
10 EXPERTS_POSTS_IN_THIS_TOPIC What is the volume of a certain rectangular solid? Bunuel 9 26 Apr 2017, 20:35
EXPERTS_POSTS_IN_THIS_TOPIC What is the volume of a certain rectangular solid? archie9 2 14 Sep 2014, 17:39
172 EXPERTS_POSTS_IN_THIS_TOPIC What is the volume of a certain rectangular solid? amod243 55 30 Aug 2017, 07:02
7 EXPERTS_POSTS_IN_THIS_TOPIC In the rectangular solid above, if each dimension EgmatQuantExpert 3 19 Mar 2017, 06:45
Display posts from previous: Sort by

If the length of each edge of a certain rectangular solid is an

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


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

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

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®.