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.
11 Apr 2018, 05:54
Kudos
Bookmarks
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:
61% (01:16) correct
39%
(01:37)
wrong
based on 488
sessions
History
Date
Time
Result
Not Attempted Yet
[GMAT math practice question] 4.11
4.11.png [ 2.07 KiB | Viewed 5996 times ]
Events \(A, B, C\) and \(D\) are all possible outcomes of an experiment. In the table above, \(P(x)\) denotes the probability that event \(x\) occurs. What is \(P(A)\)?
\(1) P(A)+P(B)+P(C)=0.75\)
\(2) P(C)+P(D)=0.25\)
Attachment:
4.11.png [ 2.07 KiB | Viewed 5996 times ]
Events \(A, B, C\) and \(D\) are all possible outcomes of an experiment. In the table above, \(P(x)\) denotes the probability that event \(x\) occurs. What is \(P(A)\)?
\(1) P(A)+P(B)+P(C)=0.75\)
\(2) P(C)+P(D)=0.25\)
11 Apr 2018, 07:06
Kudos
Bookmarks
total probability is 1
therefore, a+c+d=0.75
St1
a+0.25+c=0.75
a=0.5-c
Insufficient
St2
c+d=0.25
and we know that
a+c+d=0.75
a=0.5
Sufficient
therefore, a+c+d=0.75
St1
a+0.25+c=0.75
a=0.5-c
Insufficient
St2
c+d=0.25
and we know that
a+c+d=0.75
a=0.5
Sufficient
13 Apr 2018, 02:36
Kudos
Bookmarks
=>
Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution.
The first step of the VA (Variable Approach) method is to modify the original condition and the question. We then recheck the question.
Since \(P(A) = a = 1 – ( c + d ) – 0.25 = 0.75 – (c + d)\), then \(P(A)\) can be determined from the value of \(c + d\). Thus, the answer is \(B\).
Condition 1)
If \(P(A) = 0.5, P(B) = 0.25\) and \(P(C) = 0\), then we have \(P(A) = 0.5.\)
If \(P(A) = 0.4, P(B) = 0.25\) and \(P(C) = 0.1\), then we have \(P(A) = 0.4.\)
Thus, condition 1) is not sufficient.
Condition 2)
Since \(P(A) + P(B) + P(C) + P(D) = 1, P(B) = 0.25\) and \(P(C) + P(D) = 0.25\) from condition 2), we have \(P(A) = 0.5.\)
Thus, condition 2) is sufficient.
Therefore, the answer is B.
Answer: B
Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution.
The first step of the VA (Variable Approach) method is to modify the original condition and the question. We then recheck the question.
Since \(P(A) = a = 1 – ( c + d ) – 0.25 = 0.75 – (c + d)\), then \(P(A)\) can be determined from the value of \(c + d\). Thus, the answer is \(B\).
Condition 1)
If \(P(A) = 0.5, P(B) = 0.25\) and \(P(C) = 0\), then we have \(P(A) = 0.5.\)
If \(P(A) = 0.4, P(B) = 0.25\) and \(P(C) = 0.1\), then we have \(P(A) = 0.4.\)
Thus, condition 1) is not sufficient.
Condition 2)
Since \(P(A) + P(B) + P(C) + P(D) = 1, P(B) = 0.25\) and \(P(C) + P(D) = 0.25\) from condition 2), we have \(P(A) = 0.5.\)
Thus, condition 2) is sufficient.
Therefore, the answer is B.
Answer: B
