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 1612:00 PM EDT
-11:59 PM EDT
You’re first to know: Save $200 on GMAT prep starting tomorrow, 4/13. Get 6 official practice tests and study with real questions. Be ready to save!
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.
03 Aug 2018, 02:05
Kudos
Bookmarks
[Math Revolution GMAT math practice question]
Is 0 between x and y?
1) x-y>0
2) x^2-y^2>0
=>
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.
If we modify the question, it asks if xy < 0. Since the two conditions do not give us enough information to determine the sign of xy, both conditions together are not sufficient, and the answer is E.
Since we have 2 variables (x and y) and 1 equation, D is most likely to be the answer. So, we should consider each of the conditions on its own first.
Conditions 1) & 2)
If x = 2 and y = -1, then 0 is between x and y.
If x = 2 and y = 1, then 0 is not between x and y.
Since we don’t have a unique solution, both conditions together are not sufficient.
Therefore, E is the answer.
Answer: E
Normally, in problems which require 2 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.
Is 0 between x and y?
1) x-y>0
2) x^2-y^2>0
=>
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.
If we modify the question, it asks if xy < 0. Since the two conditions do not give us enough information to determine the sign of xy, both conditions together are not sufficient, and the answer is E.
Since we have 2 variables (x and y) and 1 equation, D is most likely to be the answer. So, we should consider each of the conditions on its own first.
Conditions 1) & 2)
If x = 2 and y = -1, then 0 is between x and y.
If x = 2 and y = 1, then 0 is not between x and y.
Since we don’t have a unique solution, both conditions together are not sufficient.
Therefore, E is the answer.
Answer: E
Normally, in problems which require 2 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.
05 Aug 2018, 19:04
Kudos
Bookmarks
[Math Revolution GMAT math practice question]
If the average (arithmetic mean) height of Bob, John and Tom is 180 cm, what is their median height?
1) Bob’s height is 175cm.
2) John’s height is 180cm.
=>
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.
When we have 3 numbers, if one of them is equal to their average, then it is also equal to their median.
Thus, condition 2) is sufficient.
Therefore, B is the answer.
Answer: B
If the average (arithmetic mean) height of Bob, John and Tom is 180 cm, what is their median height?
1) Bob’s height is 175cm.
2) John’s height is 180cm.
=>
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.
When we have 3 numbers, if one of them is equal to their average, then it is also equal to their median.
Thus, condition 2) is sufficient.
Therefore, B is the answer.
Answer: B
05 Aug 2018, 19:05
Kudos
Bookmarks
[Math Revolution GMAT math practice question]
When a positive integer n is divided by 3, what is the remainder?
1) When n is divided by 5, the remainder is 2
2) When n is divided by 6, the remainder is 2
=>
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 the divisor (6) of condition 2) is a multiple of the divisor (3) of the question, condition 2) is sufficient.
When we encounter questions related to remainders, plugging in numbers is suggested.
Condition 1)
If n = 2, then the remainder when n is divided by 3 is 2.
If n = 7, then the remainder when n is divided by 3 is 1.
Since we don’t have a unique solution, condition 1) is not sufficient.
Condition 2)
The possible values of n are
n = 2, 8, 14, 20, …
All of these values have a remainder of 2 when they are divided by 3.
Thus, condition 2) is sufficient.
Therefore, B is the answer.
Answer: B
When a positive integer n is divided by 3, what is the remainder?
1) When n is divided by 5, the remainder is 2
2) When n is divided by 6, the remainder is 2
=>
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 the divisor (6) of condition 2) is a multiple of the divisor (3) of the question, condition 2) is sufficient.
When we encounter questions related to remainders, plugging in numbers is suggested.
Condition 1)
If n = 2, then the remainder when n is divided by 3 is 2.
If n = 7, then the remainder when n is divided by 3 is 1.
Since we don’t have a unique solution, condition 1) is not sufficient.
Condition 2)
The possible values of n are
n = 2, 8, 14, 20, …
All of these values have a remainder of 2 when they are divided by 3.
Thus, condition 2) is sufficient.
Therefore, B is the answer.
Answer: B
