Amrabdelnaby wrote:Experts,

Could you please help with this?

my logic says that both statements combined are insufficient!

Our initial number line looks like this

-----r------s----t

Statement 1 tell us that s is to the right of zero, or that s is positive. Not so helpful.

Case 1: 0-----r------s----t In this case the answer is NO, 0 is not halfway between r and s

Case 2: -----r---0---s----t Here the answer is YES, 0 is halfway between r and s. Not Sufficient


Statement 2 tell us that the distance between t and r is the same as the distance between t and -s
We could reuse Case 2, (r and -s will be the same value)

Case 2:
-----r---0---s----t Again, the answer is YES
----(-s)


Case 3: -----r-----s----t--0-------(-s) Here the answer is NO
(Note that 's' is negative in this scenario and (-s) is positive)

Statement 2 alone is not sufficient.


Together, only Case 2 will satisfy both statements
-----r---0---s----t
----(-s)

(If s is positive, t must be positive, so Case 3 won't work. And if the distance between t and r is the same as the distance between t and -s, Case 1 won't work.) So together, we know that the answer to the question is YES. Answer is C

For two different approaches, check my post here:

https://www.beatthegmat.com/number-line- ... 82882.html