GMAT Question of the Day: Daily via email | Daily via Instagram New to GMAT Club? Watch this Video
close
It is currently 10 May 2021, 14:53
Register
GMAT Club Tests
Decision Tracker
My Rewards
New posts
New comers' posts

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.

Go to My Error Log Learn more
Close

Request Expert Reply

Confirm Cancel
The outside surface of a white cube with a volume 64 is painted purple
6 posts Go to First Unread Post
Print view
NEW TOPIC
POST REPLY
Downloads
My Bookmarks
Reviews
SORT BY:
Date
Kudos
Tags:
Find Similar Topics 

Show Tags
Hide Tags

User avatar
V
Bunuel
Math Expert
Joined: 02 Sep 2009
Posts: 74664
CAT Tests Top Member of the Month
The outside surface of a white cube with a volume 64 is painted purple [#permalink] New post  Updated on: 24 May 2020, 04:30
4
Bookmarks
Expert Reply
00:00
A
B
C
D
E

Difficulty:

65% (hard)

Question Stats:

60% (02:32) correct 40% (02:56) wrong based on 98 sessions

Hide Show timer Statistics

The outside surface of a white cube with a volume 64 is painted purple. The cube is then cut evenly into smaller 2x2x2 cubes, such that the sides of these cubes that were originally not facing outside remain white. What is the ratio of the total purple surface area and the total white surface area of the smaller cubes ?

A. 3:1
B. 2:1
C. 1:1
D. 1:2
E. 1:3


Are You Up For the Challenge: 700 Level Questions
ShowHide Answer
Official Answer
Official Answer and Stats are available only to registered users. Register/Login.

_________________
New to the GMAT CLUB Forum?
Posting Rules: QUANTITATIVE | VERBAL. Guides and Resources: QUANTITATIVE | VERBAL | Ultimate GMAT Quantitative Megathread | All You Need for Quant

Questions' Banks and Collection:
PS: Standard deviation | Tough Problem Solving Questions With Solutions | Probability and Combinations Questions With Solutions | Tough and tricky exponents and roots questions | 12 Easy Pieces (or not?) | Bakers' Dozen | Algebra set | Mixed Questions | Fresh Meat
DS: DS Standard deviation | Inequalities | 700+ GMAT Data Sufficiency Questions With Explanations | Tough and tricky exponents and roots questions | The Discreet Charm of the DS | Devil's Dozen!!! | Number Properties set | New DS set
MIXED: GMAT Club's Complete Questions' Bank | SEVEN SAMURAI OF 2012 | Tricky questions from previous years. | Special Questions' Directory | Best Of The Best Of 2017 | The Best Of Quant of 2016 | 20 hardest and 20 best questions of 2015 | 15 best topics of 2015 | Seven Samurai of 2012 | GMAT Probability Questions

What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics
Signature Read More

Originally posted by Bunuel on 04 Dec 2019, 00:16.
Last edited by chetan2u on 24 May 2020, 04:30, edited 1 time in total.
Edited
User avatar
G
Ansh777
Manager
Manager
Joined: 03 Nov 2019
Posts: 71
Re: The outside surface of a white cube with a volume 64 is painted purple [#permalink] New post  04 Dec 2019, 00:50
Now total number of cubes of sides 2x2x2 that can be formed from the cube of volume 64= 64/(2*2*2) =8
Total number of sides of smaller cubes combined= 6*8=48
Sides painted white:
Total number of sides of smaller cube facing outside = 4*6 (i.e. 4 faces of smaller cubes per 1 face of larger cube* Total number of sides of larger cube) = 24
Sides painted Purple:
Total number of sides of smaller cube facing inside = 48- 24=24

total purple surface area/ total white surface area of the smaller cubes = 24*(2*2)/24*(2*2) = 1:1

Answer: C
avatar
B
RajKomanapalli
Intern
Intern
Joined: 26 Jun 2017
Posts: 23
Re: The outside surface of a white cube with a volume 64 is painted purple [#permalink] New post  04 Dec 2019, 08:27
1
Kudos
Volume of Original cube : 64 units
Volume of smaller cube : 8 units

No. of Smaller cubes after cut = 64/8 = 8 cubes

all of the 8 cubes will be corner cubes and each of them will have 3 sides which were originally facing outside(White color). So the remaining 3 sides will be of purple color.

In other words, 3 faces of a cube has white color and rest of the 3 has purple color therefore, 1:1 is the answer
User avatar
B
TumharaFaizal
Intern
Intern
Joined: 07 Jul 2019
Posts: 38
Location: India
Concentration: Strategy, Technology
Schools: Desautels '23 (A$), Rice Jones '23 (A$), Tepper '23 (WL)
GMAT 1: 710 Q50 V35
GPA: 4
WE:Analyst (Computer Software)
Re: The outside surface of a white cube with a volume 64 is painted purple [#permalink] New post  24 May 2020, 04:06
The question is framed incorrectly, it does not make a sense what is written:
//
such that the sides that originally faced outside will remain white. What is the ratio of the total purple surface area and the total white surface area of the smaller cubes ?
//

If the sides originally faced outside were to remain white, then what are we painting purple in small cubes ? Its no where mentioned what we will be painting purple in small cubes.

OR

If the question asks us to compare area of Purple sides on large cube, and White on small cubes- Even then the question is wrongly framed.

Pls correct if my understanding is wrong .
User avatar
V
chetan2u
Math Expert
Joined: 02 Aug 2009
Posts: 9818
Reviews Badge Top Member of the Month
Re: The outside surface of a white cube with a volume 64 is painted purple [#permalink] New post  24 May 2020, 04:30
Expert Reply
TumharaFaizal wrote:
The question is framed incorrectly, it does not make a sense what is written:
//
such that the sides that originally faced outside will remain white. What is the ratio of the total purple surface area and the total white surface area of the smaller cubes ?
//

If the sides originally faced outside were to remain white, then what are we painting purple in small cubes ? Its no where mentioned what we will be painting purple in small cubes.

OR

If the question asks us to compare area of Purple sides on large cube, and White on small cubes- Even then the question is wrongly framed.

Pls correct if my understanding is wrong .


Edited
User avatar
V
chetan2u
Math Expert
Joined: 02 Aug 2009
Posts: 9818
Reviews Badge Top Member of the Month
Re: The outside surface of a white cube with a volume 64 is painted purple [#permalink] New post  24 May 2020, 04:33
1
Bookmarks
Expert Reply
Bunuel wrote:
The outside surface of a white cube with a volume 64 is painted purple. The cube is then cut evenly into smaller 2x2x2 cubes, such that the sides of these cubes that were originally not facing outside remain white. What is the ratio of the total purple surface area and the total white surface area of the smaller cubes ?

A. 3:1
B. 2:1
C. 1:1
D. 1:2
E. 1:3


Are You Up For the Challenge: 700 Level Questions



You can draw the sketch as shown.
As you can see that all the smaller cubes are the corner cubes that have 3 sides facing outwards and the remaining 3 sides created due to cutting.
Hence 3 sides will be purple and other 3 sides white. Similar is the case for all 8 cubes.

So the ratio is 1:1
Attachments

Untitledab.png
Untitledab.png [ 17.22 KiB | Viewed 770 times ]

GMAT Club Bot
gmatclubot
Re: The outside surface of a white cube with a volume 64 is painted purple [#permalink]
24 May 2020, 04:33
NEW TOPIC
POST REPLY
Downloads
My Bookmarks
Reviews
Moderators:
chetan2u
Math Expert
9818 posts
Bunuel
Math Expert
74663 posts
yashikaaggarwal
Senior Moderator - Masters Forum
2463 posts
generis
Senior SC Moderator
4729 posts

cron

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

Main navigation

GMAT Resources

Partners

MBA Resources

www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions