Events & Promotions
|
|
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Jun 1111:00 AM EDT
-01:00 PM EDT
TTP GMAT OnDemand gives serious students 400+ hours of expert video instruction, the full TTP course, AI support, weekly office hours, and a 715+ score guarantee—all built for elite GMAT score improvement.
Jun 1006:00 AM PDT
-06:15 PM PDT
Register for the GMAT Club Virtual MBA Spotlight Fair – the world’s premier event for serious MBA candidates. This is your chance to hear directly from Admissions Directors at nearly every Top 30 MBA program..
Jun 2207:30 PM EDT
-09:30 PM EDT
Master the GMAT with expert live instruction, a personalized study plan, and real-time support. Includes 40 hours of online classes plus 6 months of access to the TTP GMAT OnDemand video course. Class date: Mon/Wed June 22, 2026 →August 26, 2026
28 Jan 2015, 07:45
Kudos
Bookmarks
B
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
15%
(low)
Question Stats:
82% (01:28) correct
18%
(01:59)
wrong
based on 414
sessions
History
Date
Time
Result
Not Attempted Yet
From a jar containing 4 red and 2 white marbles, Lionel draws two marbles simultaneously and at random. What is the probability that he picks one marble of each color?
A. 3/5
B. 8/15
C. 7/15
D. 2/5
E. 7/30
A. 3/5
B. 8/15
C. 7/15
D. 2/5
E. 7/30
28 Jan 2015, 13:45
Kudos
Bookmarks
Hi All,
In these types of Probability questions, there's usually several different ways that you can do the math. Many books will offer an explanation that focused on the Combination Formula, but this question can be solved with Permutations. While you should practice all of the methods, you should choose whichever is most comfortable (and fastest) for you on Test Day.
We're told that we have 4 red and 2 white marbles. We're asked for the probability of pulling two marbles that are DIFFERENT colors.
Even though the question states that the marbles are drawn simultaneously, we can still think of the marbles as "1st marble" and "2nd marble"; in this way, there are two acceptable "outcomes":
1) The 1st is red and the 2nd is white
2) The 1st is white and the 2nd is red
We can calculate the probability of each occurring:
1st red = 4/6
2nd white = 2/5
(4/6)(2/5) = 8/30 chance of this happening
1st white = 2/6
2nd red = 4/5
(2/6)(4/5) = 8/30 chance of this happening
8/30 + 8/30 = 16/30 = 8/15 chance of getting the result that we wanted.
Final Answer:
GMAT assassins aren't born, they're made,
Rich
In these types of Probability questions, there's usually several different ways that you can do the math. Many books will offer an explanation that focused on the Combination Formula, but this question can be solved with Permutations. While you should practice all of the methods, you should choose whichever is most comfortable (and fastest) for you on Test Day.
We're told that we have 4 red and 2 white marbles. We're asked for the probability of pulling two marbles that are DIFFERENT colors.
Even though the question states that the marbles are drawn simultaneously, we can still think of the marbles as "1st marble" and "2nd marble"; in this way, there are two acceptable "outcomes":
1) The 1st is red and the 2nd is white
2) The 1st is white and the 2nd is red
We can calculate the probability of each occurring:
1st red = 4/6
2nd white = 2/5
(4/6)(2/5) = 8/30 chance of this happening
1st white = 2/6
2nd red = 4/5
(2/6)(4/5) = 8/30 chance of this happening
8/30 + 8/30 = 16/30 = 8/15 chance of getting the result that we wanted.
Final Answer:
GMAT assassins aren't born, they're made,
Rich
General Discussion
28 Jan 2015, 09:17
Kudos
Bookmarks
ans b 8/15...
two ways ...
1) find prob of choosing each one... 4/6*2/5*2=8/15..
2) find prob of choosing of same colour... 4/6*3/5+2/6*1/5=7/15....
so choosing one of each =1-7/15=8/15
two ways ...
1) find prob of choosing each one... 4/6*2/5*2=8/15..
2) find prob of choosing of same colour... 4/6*3/5+2/6*1/5=7/15....
so choosing one of each =1-7/15=8/15
