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vikram
 
 

if s and t are two different numbers on the number line

by vikram Sat Apr 19, 2008 5:15 am

if s and t are two different numbers on the number line, is s+t=0?

1) The distance between s and 0 is the same as the distance between t and 0
2) 0 is between s and t


I chose D, but thats not the OA, please explain.
Sudhan
 
 

by Sudhan Sat Apr 19, 2008 2:12 pm

S and t are different numbers on the line segment, Is s+t=0?
We need to know where s and t are in the line segment

Using BDACE Grid ,

2 says 0 is between s and t
In a line segment s and t are two points and 0 is between them. Let says s at -7 in the coordinate, t could be in 3 and 0 is between them. It does not give a statement that s+T=0. Insuff

1 says distance between s and o is = d( betwen t and o)
Clearly, 0 is between S and t because distance from s to 0 is equal to distance from t to 0.
This gives a way to solve for s+t=0. Hence A is sufficient

What is OA?

Thanks
guest612
 
 

reply

by guest612 Sat Apr 19, 2008 9:05 pm

The OA answer is A.

Statement 2 is insufficient because 0 is between s and t. But that means s can equal -5 and t can equal +3. In such a case, 0 is still between s and t but that does not make them equidistant from 0. Or, s and t can be -4 and +4 respectively in which case they are equidistant from 0. Therefore, this statement doesn't necessarily answer the question because it can have different results.
vikram
 
 

by vikram Sun Apr 20, 2008 1:59 am

Ahhhhh -) i mistook between to be the mid point..... thnx guys...
StaceyKoprince
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by StaceyKoprince Thu Apr 24, 2008 12:50 am

excellent! Glad your fellow studiers figured things out before we even got here! :)
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bobhelou
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Re: if s and t are two different numbers on the number line

by bobhelou Mon Nov 30, 2009 4:15 am

excuse me, but i didn't understand why statement 1 means s and t are separated by 0. (i.e. if s=t=-5, then distance from s to 0 = 5 = distance from t to 0).

what am i missing?
Ben Ku
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Re: if s and t are two different numbers on the number line

by Ben Ku Thu Dec 24, 2009 6:50 pm

bobhelou Wrote:excuse me, but i didn't understand why statement 1 means s and t are separated by 0. (i.e. if s=t=-5, then distance from s to 0 = 5 = distance from t to 0).

what am i missing?


The question states that s and t are different numbers, so they cannot both be -5. Therefore, they must be opposites of each other.
Ben Ku
Instructor
ManhattanGMAT