The Seven Keys Task

Analyze, interpret and make predictions based on theoretical probability within a practical context. Determine conditional probabilities for dependent and independent events.

You are on a game show where the winner gets a new car!  There are seven keys on a table in front of the contestants.  The first contestant gets to pick a key to try to start the car.  If the key that the first contestant picks does not start the car, then that key is thrown away and the second contestant gets to select a key from the remaining six keys.  This continues until someone selects the key that starts the car.

Which place in order (ex: first, second, last, etc) has the best theoretical probability of winning the car?  Justify your answer with mathematical reasoning and a summary statement.