A man leaves his home and walks at a speed of 12 km per hour, reaching the railway station 10 minutes after the train had departed. If instead he had walked at a speed of 15 km per hour, he would have reached the station 10 minutes before the train's departure. The distance (in km) from his home to the railway station is___
Find the average speed of a car which covers a distance of 14 km in the first 15 minutes and 10 km in the next 15 minutes.