There are 17 stations between Hyderabad and Bangalore. How many second class tickets have to be printed, so that a passenger can travel from any station to any other station?  Choose the most appropriate option.
A) 288	B) 267	C) 261	D) 211	E) 342
The total number of stations = 19   From 19 stations we have to choose any two stations and the direction of travel (i.e., Hyderabad to Bangalore is different from Bangalore to Hyderabad) in 19P₂ ways.   19P₂ = 19* 18= 
<gadget id="calculator">19* 18</gadget>
<output>342</output>
342.   Answer: 342
<result>E</result>
There are 17 stations between Hyderabad and Bangalore. How many second class tickets have to be printed, so that a passenger can travel from any station to any other station?