Question 13
An, Bình, Châu and Dũng celebrate Dũng's birthday. The first three guess Dũng's age.
An says: “Dũng is not $10$. He is $11$.”
Bình says: “Dũng is not $11$, and he is not $9$.”
Châu says: “Dũng is not $12$. He is $10$.”
One person makes two true statements, one makes exactly one true statement, and one makes two false statements. How old is Dũng?
An says: “Dũng is not $10$. He is $11$.”
Bình says: “Dũng is not $11$, and he is not $9$.”
Châu says: “Dũng is not $12$. He is $10$.”
One person makes two true statements, one makes exactly one true statement, and one makes two false statements. How old is Dũng?