A car travels 100 km at a speed of 60 km/h and returns with a speed of 40 km/h. Calculate the average speed for the whole journey.
Time taken to go =hr =hr Time taken to return = hr Total distance = (100 + 100) km = 200 km total time taken = (53 + 52)hr = hr average speed = = = 48 km/hr Hence, the average speed is 48 km/hr.
a) A train travels a distance with a speed of 40 km/h and returns with a speed of 60 km/h. Calculate the average speed of the train.
b) On a 60 km track, a train travels the first 30 km at a uniform speed of 30 km/h. How fast must a train travel the next 30 km so that the average speed is 40 km/hr for the entire trip?