I present to you a deck of 4 cards. Each card has on one side a letter of the alphabet, and on the other side a single digit from 0-9.

I propose a hypothesis that may apply to this deck:
If the letter is 'E', then the number on the other side is '4'.

I then drop the 4 cards on the table, and you see: 'B', '7', 'E', '4' (on the respective cards).

Which of the 4 cards must you turn over to verify or disprove my hypothesis?

(In reply to Solution by Joshua)

Why should the "4" have an "E" on the other side? Why couldn't it have a "C" or "D"?

Posted by Federico Kereki on 2004-12-15 17:08:10