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.
May 1410:00 AM PDT
-11:00 AM PDT
GMAT Verbal Practice question quiz. Solve 20 GMAT Focus practice questions written by GMAT Ninja. Take this GMAT practice test live with peers in timed conditions, analyze your GMAT study progress, and see where you stand in the GMAT student pool.
May 1411:30 AM EDT
-12:30 PM EDT
Is INSEAD your dream b-school and you're looking for solid prep and application strategies to get there? Check out Barkavi’s end-to-end journey to know how she did! Get insights into the INSEAD admissions process, know what Adcoms look at, and more!- May 15
08:30 AM PDT
-09:30 AM PDT
Struggling with Boldface or Paradox questions in GMAT Critical Reasoning (CR)? Boldface and Paradox CR questions are often overlooked amidst the other more common GMAT CR question types. But mastering these can significantly boost your Verbal score. - May 15
10:00 AM PDT
-11:00 AM PDT
Struggling to finish the GMAT on time? You’re not alone. The #1 reason students score lower than expected on the GMAT isn’t lack of knowledge or silly mistakes—it’s running out of time. 
May 1609:00 PM PDT
-10:00 PM PDT
Full-length FE mock with insightful analytics, weakness diagnosis, and video explanations!
May 1706:30 AM PDT
-08:30 AM PDT
We know Strengthen and Weaken questions account for more than 50% of the CR questions on the GMAT. With CR becoming even more important on GMAT Focus, it's time you strengthen your weaknesses with an approach that improves your solving time and accuracy!
May 1711:00 AM IST
-01:00 PM IST
Attend this session to learn how to Deconstruct arguments, Pre-Think Author’s Assumptions, and apply Negation Test.- May 18
11:00 AM IST
-01:00 PM IST
Attend this free GMAT Algebra Webinar and learn how to master the most challenging Inequalities and Absolute Value problems with ease. - Jun 10
06:00 AM PDT
-05:30 PM PDT
Register for the GMAT Club Virtual MBA Spotlight fair, the biggest MBA fair of the year. You will have a chance to hear Admissions directors from almost every Top 20 program speak, network with peers, and conveniently attend morning or afternoon sessions.
B
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
45%
(medium)
Question Stats:
69% (02:25) correct
31%
(02:16)
wrong
based on 483
sessions
History
Date
Time
Result
Not Attempted Yet
Set A: {1, 3, 4, 6, 9, 12, 15}
If three numbers are randomly selected from set A without replacement, what is the probability that the sum of the three numbers is divisible by 3?
A. 3/14
B. 2/7
C. 9/14
D. 5/7
E. 11/14
If three numbers are randomly selected from set A without replacement, what is the probability that the sum of the three numbers is divisible by 3?
A. 3/14
B. 2/7
C. 9/14
D. 5/7
E. 11/14
The sum of any three number from set B={3,6,12,15} would be divisible by 3. with combination method we can find how many ways we can select 3 numbers from set B. 5C3 = 10 so the probability would be 10/7
2nd method is of probability: The easy would be not selecting 1 and 4 from the set.
so P(not 1 and not 4) = P (not 1) * P(not4) => (1-1/7) * (1-1/6) => 5/7
Both Answers are wrong !!
where i'm going wrong.
Thanks
2nd method is of probability: The easy would be not selecting 1 and 4 from the set.
so P(not 1 and not 4) = P (not 1) * P(not4) => (1-1/7) * (1-1/6) => 5/7
Both Answers are wrong !!
where i'm going wrong.
Thanks
28 Dec 2010, 10:17
Kudos
Bookmarks
shrive555
Set A: {1, 3, 4, 6, 9, 12, 15}
If three numbers are randomly selected from set A without replacement, what is the probability that the sum of the three numbers is divisible by 3?
The sum of any three number from set B={3,6,12,15} would be divisible by 3. with combination method we can find how many ways we can select 3 numbers from set B. 5C3 = 10 so the probability would be 10/7
2nd method is of probability: The easy would be not selecting 1 and 4 from the set.
so P(not 1 and not 4) = P (not 1) * P(not4) => (1-1/7) * (1-1/6) => 5/7
Both Answers are wrong !!
where i'm going wrong.
Thanks
If three numbers are randomly selected from set A without replacement, what is the probability that the sum of the three numbers is divisible by 3?
The sum of any three number from set B={3,6,12,15} would be divisible by 3. with combination method we can find how many ways we can select 3 numbers from set B. 5C3 = 10 so the probability would be 10/7
2nd method is of probability: The easy would be not selecting 1 and 4 from the set.
so P(not 1 and not 4) = P (not 1) * P(not4) => (1-1/7) * (1-1/6) => 5/7
Both Answers are wrong !!
where i'm going wrong.
Thanks
Set A: {1, 3, 4, 6, 9, 12, 15}
If three numbers are randomly selected from set A without replacement, what is the probability that the sum of the three numbers is divisible by 3?
A. 3/14
B. 2/7
C. 9/14
D. 5/7
E. 11/14
How can the probability be more than 1?
Probability of an event = (# of favorable outcomes) / (total # of outcomes).
There are 5 numbers you can choose from (3, 6, 9, 12, 15) so that the sum to be divisible by 3 and there are total of 7 numbers so \(P=\frac{C^3_5}{C^3_7}=\frac{2}{7}\).
Answer: B.
General Discussion
28 Dec 2010, 10:31
Kudos
Bookmarks
ooo... i'm so dumb !! the denominator with 7C3. choosing 3 out of 7
but whats wrong with the 2nd method ?
but whats wrong with the 2nd method ?
