The train runs at the rate of 60 km. per hour for the first half and at the rate of 40 km. per hour for the second half.

The train runs at the rate of 60km .per hour for the first half and at the rate of 40km .per hour for the second half.

A train travels first 300 km at an average rate of 30 km per hour and further travels the same distance at an average rate of 60 km per hour, then the average speed over the whole distance is

A boy travels a distance of 8 km at the rate of 4 km per hour , 6 km at the rate of 3 km per hour and 4 km at the rate of 2 km per hour. What is the average speed for the entire journey ?

A car is ahead of a scooter by 30 km, car goes at the rate of 50 km an hour and the scooter goes at the rate of 60 km an hour. The scooter overtake the car after

A bike consumes 20 mL of petrol per kilometre, if it is driven at a speed in the range of 25-50 km/hour and consumes 40 mL of petrol per kilometre at any other speed. How much petrol is consumed by the bike in travelling a distance of 50 km, if the bike is driven at a speed of 40 km/hour for the first 10 km, at a speed of 60 km/hour for the next 30 km and at a speed of 30 km/hour for the last 10 km?

A person covers half of the total distance at the speed of 40 km per hour, half of the remaining at 20 km per hour and the rest at 10 km per hour. Find the average speed during the journey.

Find the ratio of speed of a cycle 15 km per hour to the speed of scooter 30km per hour-