Each of six trains – Train A through Train F – travels between exactly two cities from among six different cities – Chennai, Delhi, Kolkata, Mumbai, Bengaluru and Hyderabad – such that no two trains start from the same city and no two trains end at the same city. Further, no two trains travel between the same pair of cities. It is also known that the travel time of each train, defined as the number of hours that the train takes to travel from its origin to its destination, is a distinct positive integer less than 8.The following information is known about the origins, destinations and the travel times of the six trains:The destination of Train A is the same as the origin of Train D, but neither of these trains travel either from Delhi or to Delhi.The travel time of Train E is two hours more than that of Train C.One of the trains starts from Chennai and goes to Hyderabad, with a travel time of three hours.The travel time of Train F, which travels to Kolkata, is less than seven hours, while the travel time of the train which starts from Kolkata is two hours.The travel time of Train B, which starts from Bengaluru, is the average of the travel times of the train which starts from Mumbai and the train which starts from Hyderabad.The train which travels to Delhi starts from Kolkata, while Train D does not start from Hyderabad.