A number line is shown in the question.

r s t


r, s and t are in the number line as shown above.
r is to the left of s and s is to the left of t.

On the number line shown above, is zero halfway between r and s?

1. s is to the right of zero.
2. The distance between t and r is same as the distance between t and -s.

Please move your mouse over the darkened spot below to view the answer.

I chose B

But the correct answer is C.

With statement 2, we can infer that r = -s, because r is to the left of s in the number line. So s can not be negative. If s were negative, r would be to the right of s. So, zero should be halfway between r and s. Case closed.

Your explanation is much appreciated.
Thanks
Paddy