Answer:
Time, t = 20.87 seconds
Step-by-step explanation:
Given that,
Speed of the racehorse, v = 69 km/h = 19.16 m/s
Distance covered by the horse, d = 400 m
Let t is the time taken by the horse to cover 400 meters. It can be calculated using the definition of speed. Mathematically, the speed is given by :



t = 20.87 seconds
So, the time taken by the horse to cover 400 meters is 20.87 seconds. Hence, this is the required solution.