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.
Nov 2007:30 AM PST
-08:30 AM PST
Learn what truly sets the UC Riverside MBA apart and how it helps in your professional growth
Nov 2211:00 AM IST
-01:00 PM IST
Do RC/MSR passages scare you? e-GMAT is conducting a masterclass to help you learn – Learn effective reading strategies Tackle difficult RC & MSR with confidence Excel in timed test environment- Nov 23
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. 
Nov 2510:00 AM EST
-11:00 AM EST
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.
10 Dec 2017, 23:56
Kudos
Bookmarks
loki
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.
Since we have 3 variables, E is most likely to be the answer.
Then we need to consider both conditions 1) & 2) together.
If \(r = s = t = 1\), \(rst = 1\) and it is true.
If \(r = s = t = -1\), \(rst = -1\) and it is false.
Since we have two different cases, the answer is E.
Normally, in problems which require 2 or more additional equations, such as those in which the original conditions include 2 variables, or 3 variables and 1 equation, or 4 variables and 2 equations, each of conditions 1) and 2) provide an additional equation. In these problems, the two key possibilities are that C is the answer (with probability 70%), and E is the answer (with probability 25%). Thus, there is only a 5% chance that A, B or D is the answer. This occurs in common mistake types 3 and 4. Since C (both conditions together are sufficient) is the most likely answer, we save time by first checking whether conditions 1) and 2) are sufficient, when taken together. Obviously, there may be cases in which the answer is A, B, D or E, but if conditions 1) and 2) are NOT sufficient when taken together, the answer must be E.
20 Mar 2018, 12:13
Kudos
Bookmarks
Hi All,
We're asked if (R)(S)(T) = 1. This is a YES/NO question. We know nothing about the three variables (meaning that they could be ANYTHING). We can answer this question by TESTing VALUES.
1) (R)(S) = 1
We know nothing about the value of T….
If T = 1, then (R)(S)(T) =1(1) = 1 and the answer is YES
If T = 0, then (R)(S)(T) =1(0) = 0 and the answer is NO
Fact 1 is INSUFFICIENT
2) (S)(T) = 1
We know nothing about the value of R…
…so we'd have the same situation as in Fact 1 (YES and NO answers)
Fact 2 is INSUFFICIENT
Combined
(R)(S) = 1 and (S)(T) = 1
If R=1, S=1 and T=1, then (R)(S)(T) = 1 and the answer to the question is YES
If R=1/2, S = 2 and T = 1/2, then (R)(S)(T) = 1/2 and the answer to the question is NO.
Combined INSUFFICIENT
Final Answer:
GMAT assassins aren't born, they're made,
Rich
We're asked if (R)(S)(T) = 1. This is a YES/NO question. We know nothing about the three variables (meaning that they could be ANYTHING). We can answer this question by TESTing VALUES.
1) (R)(S) = 1
We know nothing about the value of T….
If T = 1, then (R)(S)(T) =1(1) = 1 and the answer is YES
If T = 0, then (R)(S)(T) =1(0) = 0 and the answer is NO
Fact 1 is INSUFFICIENT
2) (S)(T) = 1
We know nothing about the value of R…
…so we'd have the same situation as in Fact 1 (YES and NO answers)
Fact 2 is INSUFFICIENT
Combined
(R)(S) = 1 and (S)(T) = 1
If R=1, S=1 and T=1, then (R)(S)(T) = 1 and the answer to the question is YES
If R=1/2, S = 2 and T = 1/2, then (R)(S)(T) = 1/2 and the answer to the question is NO.
Combined INSUFFICIENT
Final Answer:
GMAT assassins aren't born, they're made,
Rich
17 Sep 2019, 06:20
Kudos
Bookmarks
loki
Is rst = 1 ?
(1) rs = 1
Since value of t is unknown
NOT SUFFICIENT
(2) st = 1
Since value of r is unknown
NOT SUFFICIENT
(1) + (2)
(1) rs = 1
(2) st = 1
rst = rs*st/s = 1/s
But value of s is unknown
NOT SUFFICIENT
IMO E
