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.
Apr 2308:00 PM PDT
-09:00 PM PDT
Video explanations + diagnosis of 10 weakest areas + 150+ short videos + study plan!
Apr 2301:30 AM EDT
-02:30 AM EDT
Struggling with GMAT Verbal as a non-native speaker? Harsh improved his score from 595 to 695 in just 45 days—and scored a 99 %ile in Verbal (V88)! Learn how smart strategy, clarity, and guided prep helped him gain 100 points.
Apr 2512:30 AM EDT
-01:30 AM EDT
At one point, she believed GMAT wasn’t for her. After scoring 595, self-doubt crept in and she questioned her potential. But instead of quitting, she made the right strategic changes. The result? A remarkable comeback to 695. Check out how Saakshi did it.
Apr 2610:00 AM EDT
-11:00 AM EDT
The Target Test Prep course represents a quantum leap forward in GMAT preparation, a radical reinterpretation of the way that students should study. Try before you buy with a 5-day, full-access trial of the course for FREE!
Apr 2711:00 AM EDT
-12:00 PM EDT
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors
Apr 2808:00 AM PDT
-11:00 AM PDT
Whether you are just beginning your MBA journey or fine-tuning your path to a 700+ score, GMAT Day is designed to give you a competitive edge.
28 Sep 2022, 03:16
Kudos
Bookmarks
C
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
95%
(hard)
Question Stats:
50% (02:26) correct
50%
(02:44)
wrong
based on 206
sessions
History
Date
Time
Result
Not Attempted Yet
A bag has 6 different pairs of socks. If 4 socks are randomly selected from the bag, what is the probability that at least 1 pair of socks is selected?
A. 15/33
B. 16/33
C. 17/33
D. 18/33
E. 19/33
A. 15/33
B. 16/33
C. 17/33
D. 18/33
E. 19/33
10 Aug 2024, 10:15
Kudos
Bookmarks
You can also solve this with probability.
Probability no matching pair is selected:
\(\frac{12}{12}*\frac{10}{11}*\frac{8}{10}*\frac{6}{9} = \frac{16}{33}\)
Here,
First sock can be any out of 12, so probability is \(\frac{12}{12} = 1\).
For second sock, we have 11 choices and 10/11 of those choices wouldn't form a pair with the one we chose first.
For third, there are 10 choices and 8 out of these wouldn't form a pair with the two socks we chose earlier.
Similarly for our last sock, 9 choices are available out of which 6 wouldn't form a pair with the 3 socks we chose earlier.
Probability at least 1 matching pair is selected:
\(1 - \frac{16}{33} = \frac{17}{33}\)
Probability no matching pair is selected:
\(\frac{12}{12}*\frac{10}{11}*\frac{8}{10}*\frac{6}{9} = \frac{16}{33}\)
Here,
First sock can be any out of 12, so probability is \(\frac{12}{12} = 1\).
For second sock, we have 11 choices and 10/11 of those choices wouldn't form a pair with the one we chose first.
For third, there are 10 choices and 8 out of these wouldn't form a pair with the two socks we chose earlier.
Similarly for our last sock, 9 choices are available out of which 6 wouldn't form a pair with the 3 socks we chose earlier.
Probability at least 1 matching pair is selected:
\(1 - \frac{16}{33} = \frac{17}{33}\)
28 Sep 2022, 05:27
Kudos
Bookmarks
Aabhash777
6 different pairs mean 12 socks, so choosing four out of these will be in 12C4 ways or 12*11*10*9/(4*3*2) or 495
Ways no pair is selected is to choose 4 socks from 6 is 6C4 ways and each selected can be either of the socks in the pair, so 6C4*2*2*2*2 or 15*16 or 240.
P=240/495=16/33
Thus, P of at least one pair of socks = 1-(16/33) or 17/33
C
