AP EAMCET201726 Apr 2017Morning ShiftMathematicsPermutation and CombinationActual
There are 10 intermediate stations on a railway line between two particular stations. The number of ways that a train can be made to stop at 3 of these intermediate stations so that no two of these halting stations are consecutive is
Options
- A56
- B20
- C126
- D120
Correct answer
A. 56
Step-by-step solution
Given that, there are 10 intermediate stations between two particular stations. Here, the train stops at only 3 stations and no two of them should be consecutive. Therefore, there are 8 stations to select these 3 stations. Hence, number of ways = ^8 C₃=56