Summer is Coming! Join the Game of Timers Competition to Win Epic Prizes. Registration is Open. Game starts Mon July 1st.

 It is currently 22 Jul 2019, 15:51 ### 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

we will pick new questions that match your level based on your Timer History

Track

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.  # Is |a| = b - c ?

Author Message
TAGS:

### Hide Tags

Intern  B
Joined: 24 Jul 2013
Posts: 29
Is |a| = b - c ?  [#permalink]

### Show Tags 00:00

Difficulty:   45% (medium)

Question Stats: 64% (01:23) correct 36% (01:25) wrong based on 70 sessions

### HideShow timer Statistics Is |a| = b - c ?

(1) a + c$$\neq{b}$$
(2) a > 0

Source: Jeff Sackman

Edit: Although the question is correctly copied from the source in which statement II is a<0, teh OA is wrong and accordingly statement II has been modified

Originally posted by longranger25 on 16 Aug 2018, 11:00.
Last edited by chetan2u on 16 Aug 2018, 23:38, edited 2 times in total.
edited the question
Senior Manager  V
Joined: 22 Feb 2018
Posts: 428
Re: Is |a| = b - c ?  [#permalink]

### Show Tags

longranger25 wrote:
Is |a| = b - c ?
(1) a + c$$\neq{b}$$
(2) a < 0

Source: Jeff Sackman

add Is |a| = b - c? in question stem
_________________
Good, good Let the kudos flow through you
Intern  B
Joined: 24 Jul 2013
Posts: 29
Re: Is |a| = b - c ?  [#permalink]

### Show Tags

Princ wrote:
longranger25 wrote:
Is |a| = b - c ?
(1) a + c$$\neq{b}$$
(2) a < 0

Source: Jeff Sackman

add Is |a| = b - c? in question stem
Intern  S
Joined: 03 Apr 2017
Posts: 45
Re: Is |a| = b - c ?  [#permalink]

### Show Tags

longranger25 wrote:
Is |a| = b - c ?

(1) a + c$$\neq{b}$$
(2) a < 0

Source: Jeff Sackman

Can't agree here.

a = -2 b=5 c =3 s1 & s2 compliant. Answer is yes.

a = -3 b=5 c=3 s1 & s2 compliant. Answer is no.

Thus answer cannot be c, as it gives 2 different answers even when taken together.
Math Expert V
Joined: 02 Aug 2009
Posts: 7763
Re: Is |a| = b - c ?  [#permalink]

### Show Tags

1
1
longranger25 wrote:
Is |a| = b - c ?

(1) a + c$$\neq{b}$$
(2) a < 0

Source: Jeff Sackman

Pl recheck the question

In present state it is E..
Either
Statement I is a+b$$\neq{c}$$
Or
Statement II would be a>0

Is |a|=b-c?
If a>0, a=b-c
If a<0, a=c-b

1) $$a+c\neq{b}............a\neq{b-c}$$
But a can be equal to c-b
Insufficient

2) a<0..
So from above
a could be equal to c-b
Insufficient

Combined.
If a=c-b... Yes otherwise No
Insufficient

E

But had statement II been a>0
Combined..
a>0, so only possibility of yes is if a=b-c
But statement I gives $$a\neq{b-c}$$
So Ans is always NO
Sufficient
Then C
_________________
Intern  B
Joined: 24 Jul 2013
Posts: 29
Re: Is |a| = b - c ?  [#permalink]

### Show Tags

I double checked the question. It is correctly copied.

I myself could not get the twisted logic behind the official explanation and hence posted the question here.

This is what the official explanation is:

Explanation: There are two ways for the equation in the question to be
true. If a is positive, then it is true if a = b - c. If a is negative, then it is true
if -a = b - c, or put another way, a = c - b. To answer the question, we need
to know whether a is positive or negative, and if the corresponding equation is
true.

Statement (1) is insufficient. a+c $$\neq{b}$$ is the same as a $$\neq{b}$$ - c, which means
that, if a is positive, the answer is "no." However, it doesn’t tell us what the
answer is if a is negative.
Statement (2) is also insufficient: it gives us the sign of a, but nothing about
how it relates to b and c.

Taken together, the statements are sufficient. Since we know a is negative,
we know the question asks, "Is a = c - b ?" (1) tells us that that is not true,
so the answer is "no." Choice (C) is correct.

chetan2u wrote:
longranger25 wrote:
Is |a| = b - c ?

(1) a + c$$\neq{b}$$
(2) a < 0

Source: Jeff Sackman

Pl recheck the question

In present state it is E..
Either
Statement I is a+b$$\neq{c}$$
Or
Statement II would be a>0

Is |a|=b-c?
If a>0, a=b-c
If a<0, a=c-b

1) $$a+c\neq{b}............a\neq{b-c}$$
But a can be equal to c-b
Insufficient

2) a<0..
So from above
a could be equal to c-b
Insufficient

Combined.
If a=c-b... Yes otherwise No
Insufficient

E

But had statement II been a>0
Combined..
a>0, so only possibility of yes is if a=b-c
But statement I gives $$a\neq{b-c}$$
So Ans is always NO
Sufficient
Then C
Intern  B
Joined: 22 Jul 2018
Posts: 9
Is |a| = b - c ?  [#permalink]

### Show Tags

chetan2u wrote:
longranger25 wrote:
Is |a| = b - c ?

(1) a + c$$\neq{b}$$
(2) a < 0

Source: Jeff Sackman

Pl recheck the question

In present state it is E..
Either
Statement I is a+b$$\neq{c}$$
Or
Statement II would be a>0

Is |a|=b-c?
If a>0, a=b-c
If a<0, a=c-b

1) $$a+c\neq{b}............a\neq{b-c}$$
But a can be equal to c-b
Insufficient

2) a<0..
So from above
a could be equal to c-b
Insufficient

Combined.
If a=c-b... Yes otherwise No
Insufficient

E

But had statement II been a>0
Combined..
a>0, so only possibility of yes is if a=b-c
But statement I gives $$a\neq{b-c}$$
So Ans is always NO
Sufficient
Then C

Hey chetan2u, why can't the answer be D?,
Statement I says $$a\neq{b-c}$$ which means it leaves us with only a+b=c, so shouldn't A be correct?
Statement ii says a>0 which leaves us with a=b-c with which we can say B is sufficient.
Are we saying C because we dont know the values of a,b and c?

Math Expert V
Joined: 02 Aug 2009
Posts: 7763
Re: Is |a| = b - c ?  [#permalink]

### Show Tags

elPatron434 wrote:
chetan2u wrote:
longranger25 wrote:
Is |a| = b - c ?

(1) a + c$$\neq{b}$$
(2) a < 0

Source: Jeff Sackman

Pl recheck the question

In present state it is E..
Either
Statement I is a+b$$\neq{c}$$
Or
Statement II would be a>0

Is |a|=b-c?
If a>0, a=b-c
If a<0, a=c-b

1) $$a+c\neq{b}............a\neq{b-c}$$
But a can be equal to c-b
Insufficient

2) a<0..
So from above
a could be equal to c-b
Insufficient

Combined.
If a=c-b... Yes otherwise No
Insufficient

E

But had statement II been a>0
Combined..
a>0, so only possibility of yes is if a=b-c
But statement I gives $$a\neq{b-c}$$
So Ans is always NO
Sufficient
Then C

Hey chetan2u, why can't the answer be D?,
Statement I says $$a\neq{b-c}$$ which means it leaves us with only a+b=c, so shouldn't A be correct?
Statement ii says a>0 which leaves us with a=b-c with which we can say B is sufficient.
Are we saying C because we dont know the values of a,b and c?

The question will give a YES under two circumstances
1) a=b-c
2) a=c-b
Any other equation would give an answer NO
So the third case
So statement 1 says it is not (1), but it can still be (2), then YES OR third case then NO
Both no and yes possible.. insufficient
Statement II a>0 so case (1) or third case possible
Insufficient

Combined only third case possible, so C
_________________
Manager  S
Joined: 06 Nov 2016
Posts: 60
Location: Viet Nam
GPA: 3.54
Re: Is |a| = b - c ?  [#permalink]

### Show Tags

longranger25 wrote:
Is |a| = b - c ?

(1) a + c $$\neq{b}$$
(2) a > 0

Source: Jeff Sackman

Edit: Although the question is correctly copied from the source in which statement II is a<0, teh OA is wrong and accordingly statement II has been modified

Is |a| = b - c ? --> Is |a|+c =b ?

(1) a + c $$\neq{b}$$

If a > 0 --> |a| = a --> a + c = |a| + c
--> |a| + c $$\neq{b}$$ --> NO

If a < 0 --> -|a| = a --> a + c = -|a| + c
--> -|a| + c $$\neq{b}$$ . Since we need to compare |a| + c and $$b$$, this statement is not sufficient.
(We can test by plugging in numbers. If a=-1, b=2, c=4 --> NO, If a=-1, b=3, c=2 --> YES => Not Sufficient)

(2) a > 0
Nothing related to b, c --> not sufficient.

Combine both statements --> we can eliminate the 2nd case in the 1st statement --> Sufficient.

_________________
（＾人＾） GMATCLUB Search for tags

Question Directory by Topic & Difficulty
Problem Solving | Data Sufficiency | Sentence Correction | Critical Reasoning | Reading Comprehension

ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION Re: Is |a| = b - c ?   [#permalink] 17 Aug 2018, 11:29
Display posts from previous: Sort by

# Is |a| = b - c ?  