Is |a| > |b|?
(1) b < -a
(2) a < 0
I am interpreting statement 1 incorrectly... Anyone willing to discuss?
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imo E.
I: a+b<0. this gives many conditions. both a and b being negative, or a is positive and b is negative but |b|>|a|, or a is negative and b is psotive but |a|>|b|.
so insufficent.
II.tells nothing about b. insuffient.
I & II:
both a and b may be negative and it is not possible to know, which one.
I: a+b<0. this gives many conditions. both a and b being negative, or a is positive and b is negative but |b|>|a|, or a is negative and b is psotive but |a|>|b|.
so insufficent.
II.tells nothing about b. insuffient.
I & II:
both a and b may be negative and it is not possible to know, which one.
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Solving by picking numbers, but would like know algebraic approach for this one.HPengineer wrote:Is |a| > |b|?
(1) b < -a
(2) a < 0
I am interpreting statement 1 incorrectly... Anyone willing to discuss?
Is |a| > |b| ?
1) b < -a
if b < 0, a < 0
pick b=-2, a = -1
-2 < -(-1) --> -2<1
|a| > |b| --> |-1| > |-2| No
pick b=-5, a=-7
-5 < -(-7) --> -5 < 7
|a| > |b| --> |-7| > |-5| Yes
statement one is not sufficient
2) a < 0
For above picked numbers we have already seen that a < 0 is not sufficient.
1) & 2) Again, both statements are not sufficient for the numbers above.
so Answer IMO is E.
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THe first statement is still getting me..
If B is less then a negative number doesn't that mean that B itself must be negative??
(1) b < -a
If B is less then a negative number doesn't that mean that B itself must be negative??
(1) b < -a
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Not necessary. If b=1 and a=-2HPengineer wrote:THe first statement is still getting me..
If B is less then a negative number doesn't that mean that B itself must be negative??
(1) b < -a
Inequality b < -a is still true 1<-(-2) i.e. 1<2
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So they are not saying A is negative but merely that there is a negative sign in front of A?
So these are the two possible scenarios for the value of A based off their statement? - (A) and -(-A)
So these are the two possible scenarios for the value of A based off their statement? - (A) and -(-A)
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|a| >|b|
can be interpreted as
if a > 0 and b > 0 ==> a > b
if a < 0 and b > 0 ==> -a > b
if a > 0 and b < 0 ==> a > -b
if a < 0 and b < 0 ==> -a > - b
so to interpret the question we need to always know the relative value of a and b wrt 0
1 b < -a doesn't tell anything about value of b and a wrt 0 .... hence insufficient
2 a < 0 doesn't tell anything about value of b wrt 0 .... hence insufficient
joining 1 and 2 we still don't know anything about value of b hence both together also insufficient. This leaves us with E.
can be interpreted as
if a > 0 and b > 0 ==> a > b
if a < 0 and b > 0 ==> -a > b
if a > 0 and b < 0 ==> a > -b
if a < 0 and b < 0 ==> -a > - b
so to interpret the question we need to always know the relative value of a and b wrt 0
1 b < -a doesn't tell anything about value of b and a wrt 0 .... hence insufficient
2 a < 0 doesn't tell anything about value of b wrt 0 .... hence insufficient
joining 1 and 2 we still don't know anything about value of b hence both together also insufficient. This leaves us with E.