Try this · No. 6 / 8

Three doors.

A car behind one door, goats behind the other two. Pick a door. The host opens a goat door. Then: stay or switch?

?% switching wins

Pick a door.

Stay: — · Switch: —

Why does switching win?

Your first pick is right one time in three, and the host opening a goat door does not change that. The other two thirds of the luck now sit behind the one door he left closed.

Try another.

No. 1How long is ten seconds?No. 2Cut a cable.No. 3Draw a perfect circle.No. 4Colour memory.No. 5Fold paper to the Moon.No. 7Daylight in Tallinn.No. 8Push the door.