SSC CPO 9 Dec 2019 Shift 2 Paper

A person travels a distance of 240 km, partly by train and the rest by bus. He takes $3\frac{1}{2}$ hours if he travels 150 km by train and the rest by bus. If he travels 140 km by bus and the rest by train, he takes $3\frac{2}{3}$ hours. What is the speed of the train?