Answer:
Step-by-step explanation:
The key fact is what are the trains doing: are they travelling toward one another or away from each other
Away from each other.
Train A has gone 50 km in 1 hour
Train B has gone 65 km in 1 hour.
They started off being 200 km apart
So their distance now is 50 + 65 + 200 = 315
Towards each other
This time they are eating into the 200 km
So you subtract
200 - 65 - 50 = 200 - 115 = 85 km.
Both trains are travelling in the same direct -- in B's direction
B - 65 + 50
200 - 15
185 km
Both trains are travelling in As direction
A - 50 + 65
200 + 15 = 215
The tricky part of this is which train is going in what direction?
As you can see, You have covered A C and D
The only one can't get is 115 (of course 315 didn't show up either).
