a train travels from station A to station B. there are 10 stations between A & B. The train stops at 3 stations only.Find the probability that no two stations are consecutive.

exclude the cases  2 and 3 stations are consecutive from total probabity:

P(C)= three stations are consecutive

      =8/10C3

P(A)= 2 stations are consecutive

       =56/10C3

thus req probability

1-P(C)-P(A)