I have this problem but I am stuck...
we have three boxes - on each one, there is an inscription
box1 - the magic recipe is here
box2 - the magic recipe is not here
box3 - the magic recipe is not in box1
assuming that $p,q,r$ are true only when the recipe is in the box1, box2, box3, respectively, write the following statements:
a- exact only one box has the recipe, the other two do not
b- only one inscription at most is true
c- exactly two boxes have the recipe, and the third is empty
Q1 - in which box is the recipe if you know that exactly only one box has the recipe, the other does not, and only one inscription at most is true?
Q2 - if two boxes have a recipe and the other is empty while only one inscription is true, which box would you pick?
Solution
The three inscriptions can be written as
$i_1 = p, i_2 = ¬q, i_3 = ¬p$
and then the statements
$a = (p ∧ ¬q ∧ ¬ r) ∨(¬p ∧ q ∧¬ r) ∨ (¬p ∧¬q ∧ r)$
$b = (¬i_1 ∧ ¬i_2 ∧ ¬i_3) ∨ i_1 ∨ i_2 ∨ i_3$
$c = (p ∧ q ∧ ¬r )∨( p ∧ r ∧ ¬q )∨ (q ∧ r ∧ ¬p )$
I would say that $Q_1 = a∧b$ and $Q_2= c ∧ b$, but trying to make the truth table for Q1 does not give me a unique answer - I guess I ve done something wrong with formatting the statements a-c? Any help?