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.
Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:
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.
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.
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!
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
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
(N/A)
Question Stats:
0%
(00:00)
correct 0%
(00:00)
wrong
based on 0
sessions
History
Date
Time
Result
Not Attempted Yet
This is one of the problem from hallelujah1234.
Quote:
A box contains 10 white and 5 black balls. 2 balls are taken out at random and put in another nox which was empty. Now a ball is drawn out of this second box at random and it turns out white. What is the probability that the other ball is black.
Let me try to rephrase the problem to see whether I understand it correctly.
OK, so the problem was given that the ball which was drawn out was white. And that is "GIVEN". So the word which means "GIVEN" tells that the probability is 100%. Is this correct? "GIVEN" means the person who picked out the ball actually saw it as white and picked that particular one. Right?
Let me know if I understand it correctly at this point.
Second question: What if I change the problem as below which ignore that fact that 2 balls are taken out first, then one was white?
A box contains 10 white and 5 black balls. Someone pulled a white ball out. What is the probability that the person pulls another ball and it is black?
So this problem is similar to the first problem right? Which has the answer 5/14.
Please comment.
Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Still interested in this question? Check out the "Best Topics" block below for a better discussion on this exact question, as well as several more related questions.
Still interested in this question? Check out the "Best Topics" block above for a better discussion on this exact question, as well as several more related questions.