Question

There is only one pilot on the island. You interview three men, Koik, Lony and Mirna. You also notice that Koik is wearing a cap.
Mirna says, “Lony’s father is the pilot. Lony is not the priest’s son.”
Koik says, “I am the priest. On this island, only priests can wear caps.”
Lony says, “I am the priest’s son. Koik is not the priest.”
Which of the following is true?

• A. Lony is not Koik’s son.
• B. Koik is the pilot.
• C. Mirna is the pilot.
• D. Lony is the priest.

Hint:

In logic puzzles with true/false constraint per person, test each character's identity and validate by eliminating inconsistencies. Use contradiction to narrow possibilities.

Answer 1

The Correct Option is B

We are told: Only priests can wear caps and Koik is wearing one.
So if Koik is telling the truth that he is the priest, then his second statement must be false. But both statements cannot be true — only one must be true. So he is not the priest.
Let’s test assumptions: Assume Koik is the pilot.
Then he is not the priest — so his second statement “only priests can wear caps” is false.
First statement “I am the priest” is also false — that breaks the rule (can’t have both statements false). Wrong
Assume Koik is the priest.
Then “I am the priest” is true, and “only priests can wear caps” is true — both true Wrong
So he is not the priest.
Assume Koik is the pilot. Try this again:
Now check Lony:
Says: “I am the priest’s son” — assume true, then “Koik is not the priest” must be false $$ Koik is priest — contradicts earlier conclusion. Wrong
Now test: Koik is the pilot
So “I am the priest” is false, “only priests can wear caps” — true. Valid. Right
Now Mirna says:
“Lony’s father is the pilot.” Let that be true. Lony is Koik’s son.
“Lony is not the priest’s son.” False. So Lony is the priest’s son. That works. Right
Now Lony:
“I am the priest’s son” — true. “Koik is not the priest” — false. Works. Right
Only Koik has one true, one false. Lony — same. Mirna — same.
Thus, Koik is the pilot is consistent with all clues.