A person travels from x to y at a speed of 40 km/h and returns by increasing his speed by 50%. What is his average speed for both trips?

Speed of person from x to y =40 km/h

Speed of person from y to x =(40×150)/100 = 60km/h

Since the distance travelled is the same

Therefore, Average Speed = (2x40x60)/40+60 = 48km/h