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

It is currently 18 May 2013, 07:44
Customize  |  Hide

A large cube 10cm on a side is composed of smaller cubes 1

  Question banks Downloads My Bookmarks Reviews  
Author Message
TAGS:
Senior Manager
Senior Manager
Joined: 02 Mar 2004
Posts: 372
Location: There
Followers: 1

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

GMAT Tests User
A large cube 10cm on a side is composed of smaller cubes 1 [#permalink] New post 15 May 2004, 16:41
00:00

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
A large cube 10cm on a side is composed of smaller cubes 1 cm on a
side. The large cube is printed red on its outside surfaces and then all the cubes are mixed in a drum. If one cube is selected randomly, which of the following is the approximate probability that the cube will have at least one red face?
A) 1:6
B) 1:5
C) 1:4
D) 1:3
E) 1:2
Senior Manager
Senior Manager
Joined: 02 Feb 2004
Posts: 369
Followers: 1

Kudos [?]: 2 [0], given: 0

GMAT Tests User
Re: PS-37 [#permalink] New post 15 May 2004, 17:13
hallelujah1234 wrote:
A large cube 10cm on a side is composed of smaller cubes 1 cm on a
side. The large cube is printed red on its outside surfaces and then all the cubes are mixed in a drum. If one cube is selected randomly, which of the following is the approximate probability that the cube will have at least one red face?
A) 1:6
B) 1:5
C) 1:4
D) 1:3
E) 1:2


# of small cubes painted on one side=surface area of large cube/are of one side of small cube=6*10*10=600/1=600
total small cubes=10*10*10=1000
P(cube will have at least one red face)=600/1000=3/5 :shock:
Senior Manager
Senior Manager
Joined: 02 Mar 2004
Posts: 372
Location: There
Followers: 1

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

GMAT Tests User
Re: PS-37 [#permalink] New post 17 May 2004, 11:33
Answer = (10^3-8^3)/10^3 = (5^3-4^3)/5^3 = (125-64)/125 ~ 1/2
Senior Manager
Senior Manager
Joined: 02 Mar 2004
Posts: 372
Location: There
Followers: 1

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

GMAT Tests User
 [#permalink] New post 17 May 2004, 13:50
well, there are 10^3 cubes. How many of them are visible? In order to count the latter, it is better count the #unvisible ones.

#unvisibles = (10-2)(10-2)(10-2) = 8^3
#visible ones(or red painted) = 10^3 - 8^3
  [#permalink] 17 May 2004, 13:50
    Similar topics Author Replies Last post
Similar
Topics:
New posts A large cube 10cm on a side is composed of smaller cubes 1 araspai 1 14 Oct 2003, 21:57
New posts A large cube 10 cm on a side is composed of cubes 1 cm on a u2lover 8 14 Jul 2006, 15:09
New posts A large cube 10 cm on a side is composed of cubes 1 cm on a ps_dahiya 4 15 Jul 2006, 00:19
New posts A large cube 10cm on a side is composed of smaller cubes 1 kripalkavi 8 18 Nov 2006, 19:11
New posts Sphere is inscribed in a cube of side length 10 cms. What is ArvGMAT 1 30 Jun 2007, 18:52
Display posts from previous: Sort by

A large cube 10cm on a side is composed of smaller cubes 1

  Question banks Downloads My Bookmarks Reviews  


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®.