In Leftwrite, every inhabitant is either a lefty or a righty. Lefties write true statements with their left hand and false statements with their right hand. Righties write false statements with their left hand and true statements with their right hand. An inhabitant wrote, "My father and I are both lefties." With the same hand, he wrote, "My father is a righty." What type is the inhabitant, what type is his father, and what hand did he write the statements with?
Both statements have the same truth value but can't both be true so both are false:
the father is a lefty.
To make the first statement false, then, the inhabitant who is writing must be a righty.
Since both statements are false, this righty must be
writing with his left hand.
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Posted by Charlie
on 2015-06-10 11:11:41 |
solution
