If |a – b| = 2, what is the value of b?

Question

(1) b < 0
(2) a > 0

Zhenek · Answer

(1) no info about a
(2) no info about b
(1)+(2): leads to  a = 2 + b , which sadly doesn't give us anything. b = -1 and a = 1, or b = -0,5 and a = 1,5

E

munnabhaimbbs · Answer

E for me.

If the question had mentioned that a and b are integers along with the condition mentioned in the question,then would the answer be C(b has to be -1 and a has to be 1 in this case)
Experts please help.
Thanks

yezz · Answer

a-b = 2 , when a>b and b-a = 2 when a<b

from 1

no info about a

from 2

no info about b

together

a>b

thus a-b = 2 , no idea about value of a thus b is not deductible ...E

AR15J · Answer

Yes munnabhaimbbs. It would be C if the question included the clause "a and b are integers". Detailed Solution : |a-b|=2=> a-b=-2 or a-b= 2 Individual statements are not sufficient. If we combine both statements -- a>0 and b<0 then a-b can never be -2 for a-b =2, if a and b are integers: there is only one possible case -- a has to be 1 and b has to be -1. if a and b are not integers: there can be many cases -- a =1.7, b =-0.3 or a=1.8, b=-0.2. So the answer of the above problem is E But, if the question is |a-b|=2 where a and b are integers, then answer will be C --------------------- +1 Kudos if you like the post

prashantrchawla · Answer

As the question simply test our ability in modulus. 
As it is not clear whether a or b are integer or not. This is how we can go ahead. Given, |a – b| = 2

Option 1: b < 0. There can be many values of b as we do not know about value of a. Insufficient. 
Option 2: a > 0. There can be many values of a as we do not know about value of b. Insufficient.

Together we can value of a = 1.5, 1 and many more values in between 
we can have value of b = -0.5, -1 and many more values in between. Hence it is not sufficient. Answer E.

spetznaz · Answer

Not an expert though , but I must say a keen observation. I almost fell into the trap ! The answer as you pointed out must be E

mvictor · Answer

nothing can be concluded from either statement, nor from both of them...
E for me.

If |a – b| = 2, what is the value of b?

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards