[RedDevil]

if you are shown the car hell yes, you know where it is.
Was that what you meant?

Marylin was right of course, but somehow it is hard to grasp.

We had a game show over here with had (I think) the same feature.
Three doors, only one had a prize in it.

You have to choose one; the chance it has the prize is 1/3.
While the door you chose stays closed, the game show host opens one of the two other doors.
If you have accidentally chosen the right door then he can open either one, but if not he must open the one remaining door that has no prize; the prize is behind the other door.

So if your choice was wrong at first, switching means you get the prize and not switching means you don't.
If your first choice was right switching means you won't get the prize, not switching means you keep it.
As the chance your first choice was right was only 1/3, you double your chances to 2/3 by switching.

The essence is this.
If all choosing was purely random the chance would stay 1/3.
But the game show host does not do a blind pull. He knows where the prize is and has to choose a door that has no prize, doubling the chance that the prize is behind the remaining door - if it weren't he would have opened that door.

But the vast majority of people will never grasp that for some reason.

Knowing this, if the prize is not that big and you don't want 1/3 of a chance to be ridiculed by your neighbours (you had the prize but you threw it away!) stay with your first choice.
If the prize is big or your neighbours are smart enough, choose the other door.

At one time the game show host accidentally opened the door with the prize. That made for a 100% chance

Oh, in the case of the Lincoln Continental and the goats the goat may get better MPG.
I'd still want the Lincoln, just to sell it and buy an electric goat.