GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 21 Aug 2018, 23:01

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

A cube has a volume of 72. If it is divided into 8 equal cubes, the

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

Hide Tags

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 48117
A cube has a volume of 72. If it is divided into 8 equal cubes, the  [#permalink]

Show Tags

New post 06 Dec 2017, 04:19
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

76% (00:49) correct 24% (01:32) wrong based on 41 sessions

HideShow timer Statistics

A cube has a volume of 72. If it is divided into 8 equal cubes, the ratio of an edge of a smaller cube to an edge of the original cube is

(A) 1 : 2
(B) 1: 3
(C) 1 : 3√2
(D) 2 : 9
(E) 1 : 9

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


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

Director
Director
User avatar
P
Joined: 18 Aug 2016
Posts: 631
Concentration: Strategy, Technology
GMAT 1: 630 Q47 V29
GMAT 2: 740 Q51 V38
GMAT ToolKit User Premium Member Reviews Badge
A cube has a volume of 72. If it is divided into 8 equal cubes, the  [#permalink]

Show Tags

New post 06 Dec 2017, 04:42
Bunuel wrote:
A cube has a volume of 72. If it is divided into 8 equal cubes, the ratio of an edge of a smaller cube to an edge of the original cube is

(A) 1 : 2
(B) 1: 3
(C) 1 : 3√2
(D) 2 : 9
(E) 1 : 9


Volume of each small cube = 72/8 = 9
Edge of each small cube = 9^1/3
Edge of Original cube = 72^1/3
\((9^(1/3)) / (8^(1/3)) * (9^(1/3))\)
1/2
A
_________________

We must try to achieve the best within us


Thanks
Luckisnoexcuse

CEO
CEO
User avatar
D
Joined: 12 Sep 2015
Posts: 2713
Location: Canada
A cube has a volume of 72. If it is divided into 8 equal cubes, the  [#permalink]

Show Tags

New post 06 Dec 2017, 10:17
Top Contributor
Bunuel wrote:
A cube has a volume of 72. If it is divided into 8 equal cubes, the ratio of an edge of a smaller cube to an edge of the original cube is

(A) 1 : 2
(B) 1: 3
(C) 1 : 3√2
(D) 2 : 9
(E) 1 : 9


Great question!
The great thing about it is that the volume of the original cube is irrelevant.
It all comes down to what happens when we divide ANY cube into 8 equal cubes.
Here's what I mean.

Take a cube and divide it into 8 equal cubes...
Image

If we let x = the length of one edge of the ORIGINAL cube....
Image

....then x/2 = the length of one edge of the SMALLER cube....
Image

What is the ratio of an edge of a smaller cube to an edge of the original cube?
Get get: x/2 : x
Divide both sides by x to get the EQUIVALENT ratio: 1/2 : 1
Multiply both sides by 2 to get the EQUIVALENT ratio: 1 : 2

Answer: A

Cheers,
Brent
_________________

Brent Hanneson – Founder of gmatprepnow.com

Image

A cube has a volume of 72. If it is divided into 8 equal cubes, the &nbs [#permalink] 06 Dec 2017, 10:17
Display posts from previous: Sort by

A cube has a volume of 72. If it is divided into 8 equal cubes, the

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

Events & Promotions

PREV
NEXT


GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| 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®.