There are 10 stations on a railway line. The number of different

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There are 10 stations on a railway line. The number of different journey tickets that are required by the authorities, is

1. 92
2. 90
3. 91
4. 93
5. None of the above

Correct Option: B

There are 10 station on railway line.
So, the number of different journey tickets between two station from given 10 stations from one side = ¹⁰C₂ = 10 x 9/2 = 45.

Similarly, number of different journey tickets from other side = 45
∴ Total number of tickets to be generated by authorities. = 45 + 45 = 90