An old man is walking on a foggy road at a speed of x km/hr. Due to low visibility, the old man see only up to 600 meters. If a car overtakes the man from the behind with the speed of 15 km/hr then the man can see the car for 216 seconds. Find the speed of the man?
1
2 km/hr
2
3 km/hr
3
4 km/hr
4
5 km/hr
5
6 km/hr