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

It is currently 16 Feb 2019, 09:43

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 in February
PrevNext
SuMoTuWeThFrSa
272829303112
3456789
10111213141516
17181920212223
242526272812
Open Detailed Calendar
  • Free GMAT Algebra Webinar

     February 17, 2019

     February 17, 2019

     07:00 AM PST

     09:00 AM PST

    Attend this Free Algebra Webinar and learn how to master Inequalities and Absolute Value problems on GMAT.
  • Free GMAT Strategy Webinar

     February 16, 2019

     February 16, 2019

     07:00 AM PST

     09:00 AM PST

    Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.

A certain box contains only blue (b), green (g) and red(r)

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

Hide Tags

 
Manager
Manager
avatar
Status: Working hard to score better on GMAT
Joined: 02 Oct 2012
Posts: 83
Location: Nepal
Concentration: Finance, Entrepreneurship
GPA: 3.83
WE: Accounting (Consulting)
A certain box contains only blue (b), green (g) and red(r)  [#permalink]

Show Tags

New post 26 May 2013, 09:45
6
15
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

63% (01:46) correct 37% (02:01) wrong based on 490 sessions

HideShow timer Statistics

A certain box contains only blue (b), green (g) and red(r) marbles. If one marble is to be picked out from the box at random, which color marble is most likely to be picked?

(1)\(\frac{b}{(g+r)}>\frac{r}{(g+b)}\)

(2) g > b

_________________

Do not forget to hit the Kudos button on your left if you find my post helpful.

Most Helpful Community Reply
VP
VP
User avatar
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1057
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
GMAT ToolKit User
Re: A certain box contains only blue (b), green (g) and red(r)  [#permalink]

Show Tags

New post 26 May 2013, 10:45
4
2
A certain box contains only blue (b), green (g) and red(r) marbles. If one marble is to be picked out from the box at random, which color marble is most likely to be picked?

(1) b/(g+r) > r/(g+b)
Case b=10 g=1 r=1
\(\frac{10}{1+1}>\frac{1}{10+1}\) in this case the answer is blue
Case b=10 g=20 r=1
\(\frac{10}{20+1}>\frac{1}{10+20}\) in this case the answer is green
Not sufficient

(2) g > b
No info about r.
Not sufficient

(1+2)
\(b(g+b)>r(g+r)\)
\(bg+b^2>rg+r^2\)
\(b^2-r^2>rg-bg\)
\((b+r)(b-r)>g(r-b)\)
CASE if \(r>b\) we have \(r-b>0\) and \(b-r<0\)
\((+)(-)>(+)(+)\)
\((-)>(+)\) Not possible
CASE if \(b>r\) we have \(b-r>0\) and \(r-b<0\)
\((+)(+)>(+)(-)\) Possible
So we find out that \(b>r\) so \(g>b>r\)
The answer is G
C
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

General Discussion
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 52902
Re: A certain box contains only blue (b), green (g) and red(r)  [#permalink]

Show Tags

New post 26 May 2013, 12:47
atalpanditgmat wrote:
A certain box contains only blue (b), green (g) and red(r) marbles. If one marble is to be picked out from the box at random, which color marble is most likely to be picked?

(1) b/(g+r) > r/(g+b)

(2) g > b

OA
after discussion


Similar question to practice from GMAT PREP: a-certain-jar-contains-only-b-black-marbles-w-white-marbles-104924.html
_________________

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

Manager
Manager
User avatar
B
Joined: 14 Jan 2013
Posts: 138
Concentration: Strategy, Technology
GMAT Date: 08-01-2013
GPA: 3.7
WE: Consulting (Consulting)
Re: A certain box contains only blue (b), green (g) and red(r)  [#permalink]

Show Tags

New post 15 Jan 2014, 15:28
2
1
atalpanditgmat wrote:
A certain box contains only blue (b), green (g) and red(r) marbles. If one marble is to be picked out from the box at random, which color marble is most likely to be picked?

(1) b/(g+r) > r/(g+b)

(2) g > b



Using one of the Bunuel Method-

b/g+r +1 > r/g+b+1

= b+g+r/g+r > b+g+r/g+b

= g+b>g+r

=b>r ( not Suff as no clue of g)

2. Not Suff, as no clue of r

1+2 , Suff
Manager
Manager
User avatar
Joined: 25 Sep 2012
Posts: 243
Location: India
Concentration: Strategy, Marketing
GMAT 1: 660 Q49 V31
GMAT 2: 680 Q48 V34
GMAT ToolKit User Reviews Badge
Re: A certain box contains only blue (b), green (g) and red(r)  [#permalink]

Show Tags

New post 17 Mar 2015, 02:57
Zarrolou wrote:
A certain box contains only blue (b), green (g) and red(r) marbles. If one marble is to be picked out from the box at random, which color marble is most likely to be picked?

(1) b/(g+r) > r/(g+b)
Case b=10 g=1 r=1
\(\frac{10}{1+1}>\frac{1}{10+1}\) in this case the answer is blue
Case b=10 g=20 r=1
\(\frac{10}{20+1}>\frac{1}{10+20}\) in this case the answer is green
Not sufficient

(2) g > b
No info about r.
Not sufficient

(1+2)
\(b(g+b)>r(g+r)\)
\(bg+b^2>rg+r^2\)
\(b^2-r^2>rg-bg\)
\((b+r)(b-r)>g(r-b)\) --------------- (A)
CASE if \(r>b\) we have \(r-b>0\) and \(b-r<0\)
\((+)(-)>(+)(+)\)
\((-)>(+)\) Not possible
CASE if \(b>r\) we have \(b-r>0\) and \(r-b<0\)
\((+)(+)>(+)(-)\) Possible
So we find out that \(b>r\) so \(g>b>r\)
The answer is G
C


I reached till (A) but then had no clue and selected (E) as answer. How did could you reason beyond that?
Intern
Intern
avatar
Joined: 03 Mar 2015
Posts: 3
GMAT ToolKit User
Re: A certain box contains only blue (b), green (g) and red(r)  [#permalink]

Show Tags

New post 10 May 2015, 08:52
1
1. b/g+r > r/g+b, add 1 both sides we get

g+b+r/g+r > g+b+r/g+b ----> b>r ..not suff
2. g> b not suff
1 & 2 Suff.
Retired Moderator
avatar
Joined: 29 Oct 2013
Posts: 257
Concentration: Finance
GPA: 3.7
WE: Corporate Finance (Retail Banking)
GMAT ToolKit User
Re: A certain box contains only blue (b), green (g) and red(r)  [#permalink]

Show Tags

New post 09 Dec 2015, 11:32
Let b, g and r be fraction of blue, green and red marbles in the box. so b+g+r=1

st1) b/(g+r) > r/(g+b)--> b/(1-b) > r/(1-r) --> (1-b)/b < (1-r)/r --> b>r. INSUF
St2) g > b INSUF

1+2--> g>b>r we know g is most likely to be picked. SUFF Ans:C
_________________

Please contact me for super inexpensive quality private tutoring

My journey V46 and 750 -> http://gmatclub.com/forum/my-journey-to-46-on-verbal-750overall-171722.html#p1367876

Board of Directors
User avatar
P
Joined: 17 Jul 2014
Posts: 2587
Location: United States (IL)
Concentration: Finance, Economics
GMAT 1: 650 Q49 V30
GPA: 3.92
WE: General Management (Transportation)
GMAT ToolKit User Premium Member Reviews Badge
Re: A certain box contains only blue (b), green (g) and red(r)  [#permalink]

Show Tags

New post 17 Mar 2016, 17:37
atalpanditgmat wrote:
A certain box contains only blue (b), green (g) and red(r) marbles. If one marble is to be picked out from the box at random, which color marble is most likely to be picked?

(1)\(\frac{b}{(g+r)}>\frac{r}{(g+b)}\)

(2) g > b


my approach:
cross multiply:
bg+b^2 > rg + r^2 - subtract r^2 from both sides then subtract bg from both sides
b^2 - r^2 > rg - bg -> factor both sides
(b+r)(b-r) > g(r-b)

note that we work with marbles - these cannot be negative.
we can conclude that r-b is negative, and b>r.
otherwise if b-r is negative, then multiplying it by a positive number would get a negative number. and a positive number (g) when multiplied by a positive number (r-b) will yield a positive number, but in this case the equation given is not true.

from statement 1, we only know that b>r. alone is insufficient.

statement 2 alone is insufficient.

1+2
we are told that b>r, and g>b. so g>b>r. green marbles are the most likely to be picked.
Director
Director
User avatar
B
Joined: 04 Jun 2016
Posts: 568
GMAT 1: 750 Q49 V43
Re: A certain box contains only blue (b), green (g) and red(r)  [#permalink]

Show Tags

New post 05 Aug 2016, 03:42
atalpanditgmat wrote:
A certain box contains only blue (b), green (g) and red(r) marbles. If one marble is to be picked out from the box at random, which color marble is most likely to be picked?

(1)\(\frac{b}{(g+r)}>\frac{r}{(g+b)}\)

(2) g > b


From stimulus we know that there are only Blue, Green and Red marbles.
So the probability of being picked will be directly proportional to the the number.
If Green has the highest number then green will have the highest probability
If Red has the highest number then red will have the highest probability
If Blue has the highest number then blue will have the highest probability

(1)\(\frac{b}{(g+r)}>\frac{r}{(g+b)}\)
This tells us that ratio of blue to other two colors is higher than ratio of red to other two colors
Meaning that Blue is more in number than Red.
But we don't know the number of green
INSUFFICIENT

(2) g > b[/quote]
This tells us that Green is more than blue
But we do not know anything about Red
INSUFFICIENT

COMBINE
GREEN > BLUE>RED

SUFFICIENT

ANSWER IS C
The probability of green is highest and red is lowest.
_________________

Posting an answer without an explanation is "GOD COMPLEX". The world doesn't need any more gods. Please explain you answers properly.
FINAL GOODBYE :- 17th SEPTEMBER 2016. .. 16 March 2017 - I am back but for all purposes please consider me semi-retired.

Intern
Intern
avatar
Joined: 02 Apr 2016
Posts: 2
Re: A certain box contains only blue (b), green (g) and red(r)  [#permalink]

Show Tags

New post 22 Oct 2017, 20:49
Another way to solve:

Let total t = b + g + r

Statement 1:
b/(g + r) > r/(g + b)
=> b/(t - b) > r/(t - r)
=> bt - br > rt - br
=> bt > rt
=> b > r

Not Suff since we don't know about g.

Statement 2:
g > b

Not Suff since we don't know about r.

Statement 1 and 2 together sufficient: g > b > r
=> g is most likely to be selected
Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 9835
Premium Member
Re: A certain box contains only blue (b), green (g) and red(r)  [#permalink]

Show Tags

New post 25 Jan 2019, 05:37
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

GMAT Club Bot
Re: A certain box contains only blue (b), green (g) and red(r)   [#permalink] 25 Jan 2019, 05:37
Display posts from previous: Sort by

A certain box contains only blue (b), green (g) and red(r)

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


Copyright

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®.