If p, s, and t are positive, is |ps - pt| > p(s - t) ?
(1) p < s
(2) s < t
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
EACH statement ALONE is sufficient.
Statements (1) and (2) TOGETHER are NOT sufficient.
题目分析:
p、s、t均为正数,判断是否满足题目,即|ps – pt|=|p(s – t)|= p|s – t|>p(s-t),两边同时除以p得|s – t|>(s - t),所以,想要判断是否满足题目中的不等式,则需要s<t即可(即左边为正,右边为负),与p无关。
因此,本题答案为(B),仅条件2可以解题,条件1不行。
p>0,等式转化为s-t和其绝对值比较
因为p始终正数
|ps – pt|=|p(s – t)|= p|s – t|>p(s-t)