In a 5 km race S gave a 500 m head start to T. If they finished the race at the same time and the speed of T is 13.5 km/h, the speed of S is:
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e.15 km/h.
Given that
In a 5 km race. S gave a 500 m head start to T.
⇒ T travels the distance = 4500 m
⇒ S travels the distance = 5000 m
The speed of T is 13.5 km/h
If they finished the race at the same time
According to the question
For the constant time, The speed is directly proportional to the distance
⇒ Speed of S/Speed of T = Distance by S/Distance by T
⇒ Speed of S/13.5 = 5000/4500 = 10/9
⇒ Speed of S = 135/9 = 15 km/h.