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

It is currently 20 Oct 2014, 04:00

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 sculptor carved a stone into a perfect cube with faces

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
VP
VP
User avatar
Joined: 25 Nov 2004
Posts: 1497
Followers: 6

Kudos [?]: 31 [0], given: 0

A sculptor carved a stone into a perfect cube with faces [#permalink] New post 02 Jan 2005, 22:28
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
A sculptor carved a stone into a perfect cube with faces measuring 100 square inches. He then carved this stone into a smaller cube with exactly one-third the volume of the original cube. The edge of the smaller cube measures most nearly

A. 7 inches.
B. 6 inches.
C. 5 inches.
D. 4 inches.
E. 3 inches.
Intern
Intern
avatar
Joined: 02 Jan 2005
Posts: 5
Location: Boston
Followers: 0

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

Linear vs. Volume Change [#permalink] New post 02 Jan 2005, 23:56
The original cube has faces with area 100 square inches, so those faces must have sides of length 10. That would give the cube a total volume of 10 ^ 3 = 1,000 cubic inches.

Since the new cube is one third the volume of the original, it has volume 1,000 / 3 = 333.33 cubic inches.

Now we have to figure out what side length would give a cube a volume of 333.33 cubic inches. Lets try some numbers from the answer choices..

7^3
= 7 * 7 * 7
= 49 * 7 =343.
Too big, but close.

6^3
= 6 * 6 * 6
= 36 * 6
= 198
Way too small.

All the other choices are even smaller, so the closest answer is 7 and the answer is A.

NOTE: The thing to understand about problems like this is that in proportional three dimensional shapes, if the volume changes by some amount, the linear measures will always change by the cubic root of that amount. In this case, the volume of the sphere changed to be 1/3 of its original, so the linear change is the cubic root of 1/3. Multiplying 10 by the cubic root of 1/3 gives 6.9 which is almost 7. Our answer checks.
_________________

Looking for a GMAT math tutor in Boston? Perhaps I can help. http://www.BostonMathTutor.com

Linear vs. Volume Change   [#permalink] 02 Jan 2005, 23:56
    Similar topics Author Replies Last post
Similar
Topics:
2 Experts publish their posts in the topic The base of a hemisphere is inscribed in one face of a cube alchemist009 4 10 Jun 2012, 16:43
Perfect Square/Cube Zarthul 1 31 May 2011, 01:46
Is X a perfect cube? (1) X is odd. (2) The number of factors Hades 1 02 Jun 2009, 21:47
If N is a perfect square and is also a perfect cube, it must joeydvivre 6 09 Nov 2006, 07:31
If a number is perfect square and perfect cube can it be 0 chiragr 2 19 May 2006, 20:58
Display posts from previous: Sort by

A sculptor carved a stone into a perfect cube with faces

  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®.