You are an explorer traveling in the Amazon rain forest. You need to explore a particularly dangerous region of the forest, so you drop by a local village of Tourguidians to hire a native as an expedition guide. The Tourguidians are the best guides to the Amazon forest. However, they are divided into 2 sub-groups: the truth tellers and the random speakers. The truth tellers will always respond to questions with the truth, while the random speakers will randomly tell the truth or lie to any question.

There are 11 Tourguidians in this particular village, 6 of whom are truth tellers, and 5 are random speakers. You don't know which person belongs to which group. You would like to find a truth teller and hire him for obvious reasons ("Umm, is this herb poisonous, Mr. Tour Guide?"). However, you are only allowed to address a total of 10 questions to the villagers. Each question may be addressed to any 1 of the 11 villagers. The restrictions are that they be Yes/No questions, and that you can not ask any question which is impossible for a truth teller to answer with a yes/no (ie. asking a truth teller what a random answerer would say to a particular question, asking paradoxes, etc. )

Devise a strategy that is guaranteed to identify a truth teller in the 11 villagers using only 10 questions. Assume that each villager know the identity/persona of his fellow villagers.

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## bushindo 14

You are an explorer traveling in the Amazon rain forest. You need to explore a particularly dangerous region of the forest, so you drop by a local village of Tourguidians to hire a native as an expedition guide. The Tourguidians are the best guides to the Amazon forest. However, they are divided into 2 sub-groups: the truth tellers and the random speakers. The truth tellers will always respond to questions with the truth, while the random speakers will randomly tell the truth or lie to any question.

There are 11 Tourguidians in this particular village, 6 of whom are truth tellers, and 5 are random speakers. You don't know which person belongs to which group. You would like to find a truth teller and hire him for obvious reasons ("Umm, is this herb poisonous, Mr. Tour Guide?"). However, you are only allowed to address a total of 10 questions to the villagers. Each question may be addressed to any 1 of the 11 villagers. The restrictions are that they be Yes/No questions, and that you can not ask any question which is impossible for a truth teller to answer with a yes/no (ie. asking a truth teller what a random answerer would say to a particular question, asking paradoxes, etc. )

Devise a strategy that is guaranteed to identify a truth teller in the 11 villagers using only 10 questions. Assume that each villager know the identity/persona of his fellow villagers.

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