Two trains started at 7AM from the same point. The first train travelled north at a speed of 80km/h and the second train travelled south at a speed of 100 km/h.

Q. Two trains started at 7AM from the same point. The first train travelled north at a speed of 80km/h and the second train travelled south at a speed of 100 km/h. The time at which they were 540 km apart is__________ AM.

(A) 9

(B) 10

(C) 11

(D) 11.30

Ans: 10

Explanation:

The correct option is 10
According to the concept of relative speed in opposite direction speeds should be added
Time of activity=Sum of distance/Sum of speeds

=540/(100+80)=540/180

=3 hours from 7am=10am