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sk
 
 

DS - Position of numbers on number line

by sk Thu Aug 07, 2008 10:20 am

If S and T are two different numbers on the number line, is S+T equal to 0?

1). The distance between S and 0 is same as that of distance between T and 0.

2). 0 is between S and T.
banerjee
 
 

by banerjee Sat Aug 09, 2008 3:25 am

If S and T are two different numbers on the number line, is S+T equal to 0?

1). The distance between S and 0 is same as that of distance between T and 0.

2). 0 is between S and T.


(1) alone is clearly insufficient because S and T can very well be on the same side or on opposite sides of the number line.

(2) alone is insufficient as well since we don't know the individual distances of S and T from 0.

However, combining 1 & 2, we can say that YES, S+T=0.

Hence, answer seems to be C.
Guest
 
 

by Guest Sat Aug 09, 2008 7:36 pm

Isn't statement 1 sufficient because it says that the integers are different?
Guest
 
 

by Guest Mon Aug 11, 2008 5:11 pm

banerjee Wrote:If S and T are two different numbers on the number line, is S+T equal to 0?

1). The distance between S and 0 is same as that of distance between T and 0.

2). 0 is between S and T.


(1) alone is clearly insufficient because S and T can very well be on the same side or on opposite sides of the number line.

(2) alone is insufficient as well since we don't know the individual distances of S and T from 0.

However, combining 1 & 2, we can say that YES, S+T=0.

Hence, answer seems to be C.


I thought the statement 1 by itself already sufficient enough to answer the question.
since in the question stem said "If S and T are two different number", and in statement 1:The distance between S and 0 is same as that of distance between T and 0. so if S=-1or 1, T=1or -1, Both S and T have the same dis. S(-1)+T(1)=0. ---yes, S(1)+T(-1)=0...yes, if you try 2 or -2 for S and T, the answer still will be yes. so, My answer will be A.
Banerjee
 
 

by Banerjee Tue Aug 12, 2008 2:47 am

Yes, I agree with you. While solving the question, I overlooked the word "different". Thanks for the correction.
rfernandez
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by rfernandez Fri Aug 22, 2008 1:11 am

Agreed... the answer is A. Nice work!
Guest
 
 

by Guest Sat Aug 30, 2008 5:19 am

Here in option two : 0 is between S & T..so shdnt that be also suffcient ?
If 0 is between S&T isnt it the midpoint of S & T ?
Asiddy
 
 

by Asiddy Wed Sep 03, 2008 11:27 pm

I agree, should the answer be D

whats the OA?
RonPurewal
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by RonPurewal Fri Sep 26, 2008 6:48 am

Anonymous Wrote:Here in option two : 0 is between S & T..so shdnt that be also suffcient ?
If 0 is between S&T isnt it the midpoint of S & T ?


goodness gracious, no.

just as in normal parlance, "between" only means "between", and carries no connotations of equidistance from the two points.
for instance, it's quite true that 1 is between 0 and 100, but obviously false that 1 is the midpoint between 0 and 100.

same thing with statement two. if 0 is between s and t, then all this means is that one of s and t is positive and the other is negative. that is all; there's nothing barring possibilities such as s = -1,000,000 and t = 1.