AP Police SI Exam Prelims 2016 Paper 1 (Mental Ability)

A person travels 120 km by steamer, 450 km by rail and 60 km by taxi in a journey. The speed of the train is thrice that of the taxi and $1\frac{1}{2}$ times that of the steamer. If the time taken for his entire journey is 18 hours, then the speed of the train (in km/hr) is