求助 一道prep数学题

littlestoner

有一张图，是一个数轴，从左到右依次是r,s,t三点
题目是DS题：
Is zero at the halfway of 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

答案是C好像，但我觉得应该是B阿？有xdjm遇到过这道题还有印象的么？谢谢

dbearwangs

如果0再S的右侧，则2完全有可能，比如r＝－4，s＝－2，t＝－1，－s＝2

littlestoner

多谢多谢，呵呵，难怪想半天没想清楚，原来潜意识里把t当作大于-s了，呵呵，：）