gmat740 wrote:----r---- s---- t---
On the number line shown, is zero halfway between r and s?
1). s is to the right of zero
2). the distance between t and r is the same as the distance between t and -s.
[spoiler]OA-C
IMO-B[/spoiler]

I almost made the same mistake as you did, but consider this:

r=-5, s=-3, t=-1. -s=3, so this would work with 2, but would not be sufficient to answer the question.

Good question Karan. I got tricked as well.

Can someone explain this in detail please...I am having trouble understanding the concept here.

taking all numbers to be positive I get -r = s. After that I seem to derail

Thanks

ssmiles08 wrote:Can someone explain this in detail please...I am having trouble understanding the concept here.

taking all numbers to be positive I get -r = s. After that I seem to derail

Thanks

We basically need to find out if '0' comes in between r & s on the number line.

The question stem does not say that r,s & t are positive integers. So, given the information in Statement 2, if t=-1 s=-3 & r=-5, then -s=3. The distance between t & r is 4 & the distance between t & -s is also 4. But 0 is not between r & s. Now, if we consider t=1, s=3 & r=5, then -s=-3. The distance between t & r is 4 & the distance between t & -s is also 4. But in this condition 0 comes in between r & s. So, this statement alone is not sufficient.

Both statements combined allows us to answer the question. Hence C. Hope this helps you get back on track

Vemuri wrote:

ssmiles08 wrote:Can someone explain this in detail please...I am having trouble understanding the concept here.

taking all numbers to be positive I get -r = s. After that I seem to derail

Thanks

We basically need to find out if '0' comes in between r & s on the number line.

The question stem does not say that r,s & t are positive integers. So, given the information in Statement 2, if t=-1 s=-3 & r=-5, then -s=3. The distance between t & r is 4 & the distance between t & -s is also 4. But 0 is not between r & s. Now, if we consider t=1, s=3 & r=5, then -s=-3. The distance between t & r is 4 & the distance between t & -s is also 4. But in this condition 0 comes in between r & s. So, this statement alone is not sufficient.

Both statements combined allows us to answer the question. Hence C. Hope this helps you get back on track

I see it!! thank you!