Question

The distance between two station is 425 km. Two train start simultaneously from these stations on a parallel tracks to cross each other. The speed of one trains is greater than the other is 5 km/ hr. If the distance between two train after 3 hours of their start is 20 km, find the speed of each train

Answer 1

Given that distance between two stations= 425 km
Let the speed of the first train be x km/hr
Then the speed of other train is (x+5) km/hr
Distance travelled by first train in 3 hours = 3 × x km/hr = 3x km 
Distance travelled by second train in 3 hours = 3× (x+5) km/hr = 3x +15 km
Also given that distance between the trains after three hours= 20
By given data 
3x + 20 + 3x+15 = 425
6x + 35 = 425
6x = 425 - 35 = 390
x = 390 / 6 = 65 km/hr 
Therefore speed of first train = x = 65 km/hr
speed of second train = x + 5 = 65 + 5 = 70 km/hr 

please mark as brilliancy..

Answer 2

Answer: 65km/hr & 70km/hr

Step-by-step explanation:

Let speed of one train be x km/hr.

Then, speed of other train

= x+5 km/hr.

Distance travelled by 1st train in 3hrs = 3x km.

Distance travelled by 2nd train in 3hrs = 3(x+5)km = 3x+15km.

3x + 3x+15 + 20 = 425

6x+35 = 425

6x = 425-35

6x = 390

x = 65

Hence, speed of 1st train = 65km/hr

Speed of 2nd train = 65+5 = 70km/hr.