There are 14 Railway stations along a line. Number of ways of selecting 3 stations out of them to stop the train such that no two stops are adjacent is

Number of ways of selecting r non consecutive things from n different things in a line is${ }^{n-r+1}{C}_r$

Number of ways of selecting 3 stations out of 14 railway stations to stop the train such that no two stops are adjacent is ${=}^{n-2}{c}_3{=}^{12}{c}_3=220$