Given distance=360 km. Let the speed of the train be x km/hr.Speed when increased by 5 km/hr =(x+5) km/hrx360​−(x+5)360​=1x(x+5)[360x+1800−360x]​=1x2+5x−1800=0x2+45x−40x−1800=0x(x+45)−40(x+45)=0(x−40)(x+45)=0x=40,−45The speed of the train is 40 km/hr.