Question

The distance between two stations is 425km. Two trains start simultaneously from these stations
on parallel tracks to cross each other. The speed of one of them is greater than that of the other
by 5km/h. If the distance between the two trains after 3h of their start is 20kın, find the speed of
each train. Check your solution​

Answer 1

Let the trains be A and B.

Speed of A = x km/h

Speed of B = (x+5) km/h

After 3 hours,

distance travelled by A = 3x km

distance travelled by B = 3(x+5) km = 3x+15 km

now distance between them is 20km

So 3x + (3x+15) + 20 = 425

$\sf6x + 35 = 425$

$\sf6x = 425 – 35 = 390$

$\sf x = 390/6 = 65 km/h$

$\sf x + 5 = 65+5 = 70 km/h$

Speed of the trains are 65 km/h and 70 km/h.