Question

two trains start simultaneously in opposite directions from two stations A and B which are 400 km apart. the speed of one train is 5 km/h greater than the other. After 2 hours if the distance between the two trains is 90 km , find the speed of the faster train​

Answer 1

Answer:

Let the trains start from station A and station B respectively.

Let the first train start from station A and the second train start from station B at the same time and move towards each other.

Let the speed of the first train be x km/hr

∴ the speed of the second train =(x+20) km/hr

Distance travelled by first train in 2 hours =2x km

Distance travelled by second train in 2 hours =2(x+20) km =(2x+40) km

Given, distance between two stations =300 km

According to the given condition, we have

Distance travelled by first train + Distance travelled by second train +20=300

i.e., 2x+(2x+40)+20=300

4x+60=300

4x=300−60 ....[Transposing 60 to RHS]

4x=240

Thus, x=

4

240

=60

∴ Speed of the first train =60 km/hr and

speed of the second train =(60+20) krn/h =80 km/hr.