Stations X and Y are connected by two separate, straight, parallel rail lines that are 250 miles long. Train P and train Q simultaneously left Station X and Station Y, respectively, and each train traveled to the other’s point of departure. The two trains passed each other after traveling for 2 hours. When the two trains passed, which train was nearer to its destination?
(1) At the time when the two trains passed, train P had averaged a speed of 70 miles per hour.
(2) Train Q averaged a speed of 55 miles per hour for the entire trip.
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.
我选了 Ｄ ， 理由如下，ａ 说了 在相遇前ｐ的速度，所以相遇点为 ｐ的速度乘２ ．求出具体点．可得具体位置
ｂ 说Ｑ的全程速度，平均速度．那么相遇点位 Ｑ*２ 距离它的出发点的具体位置， 也可以求出具体位置，ｓｏ， 应该为Ｄ答案阿
前面ｎ多牛 说 为 Ａ ，为什么Ｂ不行啊？
请教数学高手． | 
