The Game will do it for you as the settings you done for the route would vary on how long it would take to get from point A - Point B.
To give you a fair idea the Ticket Price to fly from London heathrow to Frankfurt Airport would cost the Following, but keep in mind that the tickets shown are Auto price so the A.I will show you the best price for people to fly with you but don't worry you can set the price to whatever you want.
economy class 174.24
premium economy class 384.48
Business Class 522.73
First class 1045.45