|
|
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.
17 Jun 2022, 20:55
Kudos
Bookmarks
E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
55%
(hard)
Question Stats:
60% (02:15) correct
40%
(01:56)
wrong
based on 58
sessions
History
Date
Time
Result
Not Attempted Yet
Is |a - c| + |a| = |c|?
(1) ab > bc
(2) bc < 0
(1) ab > bc
(2) bc < 0
Pure algebraic questions like this one are no longer part of the GMAT Data Sufficiency syllabus.
For relevant Data Sufficiency questions, please check the Data Sufficiency forum:
Data Sufficiency Forum
Data Sufficiency Forum
18 Jun 2022, 12:07
Kudos
Bookmarks
nahid78
Statement 1 Alone:
We know nothing about b, so this may result in \(a > c\) or \(a < c\) depending on the sign of b.
If \(a > c > 0\), then Left side = \(2a - c\) and Right side = \(c\), equating gives \(a = c\) which is not possible. Then the statement can be answered with a "no" for this case.
If \(0 < a < c\), then we have \(c - a + a = c\) and \(c = c\), so the statement is true in this case. Since we have both "yes" and "no" cases, this statement is insufficient.
Statement 2 Alone:
b is not really our concern so this statement provides no value (we can interpret this statement as b and c have opposite signs). Insufficient.
Both Statements Combined:
If b > 0, then a > c while c < 0. Then we can have \(a > 0 > c\), plugging in the questioned equation gives \(a - c + a = -c\) and \(a = 0\), which is a possible scenario. Then this case alone already provides possible "yes" and "no" scenarios. Insufficient.
Answer: E
20 Jun 2022, 20:28
Kudos
Bookmarks
JerryAtDreamScore
Hello JerryAtDreamScore can you please explain why while testing 0 < a < c , the new equation (c - a + a = c) will have different signs only for the first c and a and not the following a and c as well? something like c - a - a = - c ... I imagine because the other c and a terms are alone inside the absolute value and do not "interact" with other terms, something actually happening in |a - c|?
Please help me clarify this better than just a vague intuition
