There are 18 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?	Choices
A) 120	B) 380	C) 400	D) 800	E) 250
Explanation:   The total number of stations = 20   From 20 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 ²⁰P₂ ways.   20P2 = 20 * 19= 
<gadget id="calculator">20 * 19</gadget>
<output>380</output>
380.   Answer: 380
<result>B</result>
There are 18 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?