Two trains, one starting in Calgary and the other in Edmonton, travel towards one another. The Edmonton train travels at 120 km/h toward Calgary, while the Calgary train travels at 140 km/h towards Edmonton. If the trains are 285 km apart, how far from Calgary will the trains pass each other?

Answer 1

I will assume that the trains are 285 km apart, (Google map says it is 300 km)
so after a time of t hours, the distance between them is
285 - 140t - 160t = 285 - 300t
we want that to be zero,
285 - 300t = 0
t = 19/20 hrs.

distance from Calgary = (140)(19/20) km = ...

Answer 2

another perspective;
The relative speed of the calgary departing train is 260km/hr
the distance they both combined travel is 285km
time to meet: 285/260 hr= 57/52 hr
how far from Calgary? 140km/hr * 57/52 hr = ....
On Reiny's response, there is a typo, which affects the cacluations. the 160 should be 120. check that.

Answer 3

At the point where they pass, the total distance traveled(Dc+De) = 285 km,
140T + 120T = 285,
T = 1.1 hours at the point where they pass,

Dc = 140*T = 140*1.1 = 153.5 km = Distance from Calgary.