Puzzle n°30 (*) - May I go out ? Homepage  

Three very clever somalis (Alaska, Brownie and Calisson) were held captive by a strange guard.
One day, this guard decided to paint a sign on the neck of each somali,
in such a way that they couldn't see their own marking but could see the one of the others.

3 somalis

He told them : "Each one of you has either a circle or a cross on his neck.
At least one of you has a cross.
If you manage, through your own reasoning and without communicating with the two others,
to deduce that you do have a cross drawn on your neck, you may go out freely !
However, if you ever try to go out with a circle on your neck, I'll catch you and you'll be my prisoner forever."

The guard wanted the problem to be difficult for them, but at the same time,
he wanted to leave each one of the three somalis the same chance.
Therefore he drew 3 crosses (but the somalis didn't know !)

How will each one of them be able to answer the crucial question "May I go out ?"...
Would you have succeeded in their place ?

... I'm giving up ...


© Marie-Bernadette Pautet, 2005-2019
Last page update: 10.6.2008