Question

If a boy runs at the speed of 20 km/hr and crosses a bridge in 15 minutes, then what is the length of the bridge?

A 5000 metres Correct Answer Incorrect Answer
B 4500 metres Correct Answer Incorrect Answer
C 5500 metres Correct Answer Incorrect Answer
D 6000 metres Correct Answer Incorrect Answer

Solution

Let us assume the length of the bridge be 'L' The speed of the boy = [20 × (5/18)] = (100/18) m/s The time = 15 minutes = (15 × 60) = 900 seconds L= [900 × (100/18)] = 5000 metres

Practice Next
×
×