

7. 
A
train leaves the station traveling due east at a rate of 45 miles
per hour. A second train leaves a different station an hour later,
traveling due west on the same track, going 60 miles per hour. If
the stations are 255 miles apart, how many miles from the halfway
point between the stations will the trains collide? 
 (A) 
0 
 (B) 
5 
 (C) 
7.5 
 (D) 
12.5 
 (D) 
25 
