Question

If there are 10 stations on the route and the train has to be stopped at four of them, then the number of ways in which the train can be stopped so that at least two stopping stations are consecutive?

Answer 1

Step-by-step explanation:

Required number of ways,

= Total - number of ways in which two stopping stations are consecutive.

$= \: ¹⁰C_{4} - ⁷C_{3}$

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Answer 2

Step-by-step explanation:

The number of ways in which the train can be stopped so that atleast two stopping stations are consecutive is

Let two consecutive stations be a single unit then

Required answer will be

9 C 3