Question

A bus covers a certain distance in 3 hours 20 minutes at an average speed of 45 km per hour. How much time will it take to cover the same distance at a speed of 50 km per hour?

Answer 1

Time taken to cover the distance at a speed of 45 km/h = 3 h 20 min
Time taken to cover the distance at a speed of 1 km/h = 45 $\times$ 3.33 h [Less speed, more time taken]
(20 min = 0.33 hour)
∴ Time taken to cover the distance at a speed of 50 km/h = $\frac{45\times 3.33}{50}$h ≈ 3 h [More speed, less time taken]