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Four friends - A, B, C and D - belong to an island, in which each person belongs to one of the three tribes - Truth tellers, Alternators and Liars. Truth tellers always tell the truth, Alternators alternate between true and false statements, in any order and Liars always lie. A, B, C and D earn their respective livelihoods as a Banker, a Journalist, an Engineer and a Doctor, not necessarily in the same order. When asked about the tribes and how they earn their livelihoods, each of them made exactly three statements. B made his first and third statements in the local language, which was incomprehensible, but made his second statement in English. However, A, C and D made all their statements in English.
 
A:
Statement 1: B’s first statement is that, “C is either a Journalist or a Doctor.”
Statement 2: C is not a Truth teller.
Statement 3: B is an Engineer.

B:
Statement 1: Aabra ka Daabra.
Statement 2: Atleast one of my statements is false.
Statement 3: Daan a kun.

C:
Statement 1: A is a Doctor.
Statement 2: B’s third statement is that, “D is a truth teller.”
Statement 3: D is neither a Journalist nor an Engineer.

D:
Statement 1: C made exactly one true statement.
Statement 2: Exactly two of us are truth tellers.
Statement 3: C is a Journalist.
 
Among A, B, C and D, at least one person of each tribe is present.
 
 
Q. Who is the Banker? 
  • a)
     A
  • b)
    B
  • c)
    C
  • d)
    D
  • e)
    Cannot be determined
Correct answer is option 'D'. Can you explain this answer?
Verified Answer
Four friends - A, B, C and D - belong to an island, in which each pers...
Solution: Consider the table obtained in the solution to the first question. D is the banker.
Hence, option 4.
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Most Upvoted Answer
Four friends - A, B, C and D - belong to an island, in which each pers...
Solution: Consider the table obtained in the solution to the first question. D is the banker.
Hence, option 4.
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Community Answer
Four friends - A, B, C and D - belong to an island, in which each pers...
Understanding the Statements
To determine who the Banker is among A, B, C, and D, we analyze their statements:
A's Statements:
- Statement 1: B's first statement claims C is either a Journalist or a Doctor.
- Statement 2: C is not a Truth teller.
- Statement 3: B is an Engineer.
B's Statements:
- Statement 1: (Incomprehensible)
- Statement 2: At least one of my statements is false.
- Statement 3: (Incomprehensible)
C's Statements:
- Statement 1: A is a Doctor.
- Statement 2: B's third statement claims D is a Truth teller.
- Statement 3: D is neither a Journalist nor an Engineer.
D's Statements:
- Statement 1: C made exactly one true statement.
- Statement 2: Exactly two of us are Truth tellers.
- Statement 3: C is a Journalist.
Analysis of Truthfulness
1. D's Claim: If D's Statement 1 is true, then C has one true statement, which can only be Statement 3, meaning C is a Journalist. This makes D's Statement 2 true, indicating that D is a Truth teller.
2. C's Statement: If C is a Journalist, D's Statement 3 (C is not a Journalist) must be false, making D a Liar.
3. B's Statements: Since B claims at least one of his statements is false, if he is an Alternator, then we can deduce that he is not telling all truths or lies.
4. A's Statements: A's Statement 2 (C is not a Truth teller) aligns with our deductions.
Thus, we determine:
- A is the Liar (since his statements contradict the others).
- B is the Alternator.
- C is the Truth teller.
Conclusion
With A as the Liar, B as the Alternator, and C as the Truth teller, D must be the Banker, as he is the only one left to fulfill the role.
Thus, the answer is D.
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Four friends - A, B, C and D - belong to an island, in which each person belongs to one of the three tribes - Truth tellers, Alternators and Liars. Truth tellers always tell the truth, Alternators alternate between true and false statements, in any order and Liars always lie. A, B, C and D earn their respective livelihoods as a Banker, a Journalist, an Engineer and a Doctor, not necessarily in the same order. When asked about the tribes and how they earn their livelihoods, each of them made exactly three statements. B made his first and third statements in the local language, which was incomprehensible, but made his second statement in English. However, A, C and D made all their statements in English.A:Statement 1: B’s first statement is that, “C is either a Journalist or a Doctor.”Statement 2: C is not a Truth teller.Statement 3: B is an Engineer.B:Statement 1: Aabra ka Daabra.Statement 2: Atleast one of my statements is false.Statement 3: Daan a kun.C:Statement 1: A is a Doctor.Statement 2: B’s third statement is that, “D is a truth teller.”Statement 3: D is neither a Journalist nor an Engineer.D:Statement 1: C made exactly one true statement.Statement 2: Exactly two of us are truth tellers.Statement 3: C is a Journalist.Among A, B, C and D, at least one person of each tribe is present.Q. Who is the Banker?a)Ab)Bc)Cd)De)Cannot be determinedCorrect answer is option 'D'. Can you explain this answer? for UPSC 2025 is part of UPSC preparation. The Question and answers have been prepared according to the UPSC exam syllabus. Information about Four friends - A, B, C and D - belong to an island, in which each person belongs to one of the three tribes - Truth tellers, Alternators and Liars. Truth tellers always tell the truth, Alternators alternate between true and false statements, in any order and Liars always lie. A, B, C and D earn their respective livelihoods as a Banker, a Journalist, an Engineer and a Doctor, not necessarily in the same order. When asked about the tribes and how they earn their livelihoods, each of them made exactly three statements. B made his first and third statements in the local language, which was incomprehensible, but made his second statement in English. However, A, C and D made all their statements in English.A:Statement 1: B’s first statement is that, “C is either a Journalist or a Doctor.”Statement 2: C is not a Truth teller.Statement 3: B is an Engineer.B:Statement 1: Aabra ka Daabra.Statement 2: Atleast one of my statements is false.Statement 3: Daan a kun.C:Statement 1: A is a Doctor.Statement 2: B’s third statement is that, “D is a truth teller.”Statement 3: D is neither a Journalist nor an Engineer.D:Statement 1: C made exactly one true statement.Statement 2: Exactly two of us are truth tellers.Statement 3: C is a Journalist.Among A, B, C and D, at least one person of each tribe is present.Q. Who is the Banker?a)Ab)Bc)Cd)De)Cannot be determinedCorrect answer is option 'D'. Can you explain this answer? covers all topics & solutions for UPSC 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Four friends - A, B, C and D - belong to an island, in which each person belongs to one of the three tribes - Truth tellers, Alternators and Liars. Truth tellers always tell the truth, Alternators alternate between true and false statements, in any order and Liars always lie. A, B, C and D earn their respective livelihoods as a Banker, a Journalist, an Engineer and a Doctor, not necessarily in the same order. When asked about the tribes and how they earn their livelihoods, each of them made exactly three statements. B made his first and third statements in the local language, which was incomprehensible, but made his second statement in English. However, A, C and D made all their statements in English.A:Statement 1: B’s first statement is that, “C is either a Journalist or a Doctor.”Statement 2: C is not a Truth teller.Statement 3: B is an Engineer.B:Statement 1: Aabra ka Daabra.Statement 2: Atleast one of my statements is false.Statement 3: Daan a kun.C:Statement 1: A is a Doctor.Statement 2: B’s third statement is that, “D is a truth teller.”Statement 3: D is neither a Journalist nor an Engineer.D:Statement 1: C made exactly one true statement.Statement 2: Exactly two of us are truth tellers.Statement 3: C is a Journalist.Among A, B, C and D, at least one person of each tribe is present.Q. Who is the Banker?a)Ab)Bc)Cd)De)Cannot be determinedCorrect answer is option 'D'. Can you explain this answer?.
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However, A, C and D made all their statements in English.A:Statement 1: B’s first statement is that, “C is either a Journalist or a Doctor.”Statement 2: C is not a Truth teller.Statement 3: B is an Engineer.B:Statement 1: Aabra ka Daabra.Statement 2: Atleast one of my statements is false.Statement 3: Daan a kun.C:Statement 1: A is a Doctor.Statement 2: B’s third statement is that, “D is a truth teller.”Statement 3: D is neither a Journalist nor an Engineer.D:Statement 1: C made exactly one true statement.Statement 2: Exactly two of us are truth tellers.Statement 3: C is a Journalist.Among A, B, C and D, at least one person of each tribe is present.Q. Who is the Banker?a)Ab)Bc)Cd)De)Cannot be determinedCorrect answer is option 'D'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of Four friends - A, B, C and D - belong to an island, in which each person belongs to one of the three tribes - Truth tellers, Alternators and Liars. Truth tellers always tell the truth, Alternators alternate between true and false statements, in any order and Liars always lie. A, B, C and D earn their respective livelihoods as a Banker, a Journalist, an Engineer and a Doctor, not necessarily in the same order. When asked about the tribes and how they earn their livelihoods, each of them made exactly three statements. B made his first and third statements in the local language, which was incomprehensible, but made his second statement in English. However, A, C and D made all their statements in English.A:Statement 1: B’s first statement is that, “C is either a Journalist or a Doctor.”Statement 2: C is not a Truth teller.Statement 3: B is an Engineer.B:Statement 1: Aabra ka Daabra.Statement 2: Atleast one of my statements is false.Statement 3: Daan a kun.C:Statement 1: A is a Doctor.Statement 2: B’s third statement is that, “D is a truth teller.”Statement 3: D is neither a Journalist nor an Engineer.D:Statement 1: C made exactly one true statement.Statement 2: Exactly two of us are truth tellers.Statement 3: C is a Journalist.Among A, B, C and D, at least one person of each tribe is present.Q. Who is the Banker?a)Ab)Bc)Cd)De)Cannot be determinedCorrect answer is option 'D'. Can you explain this answer?, a detailed solution for Four friends - A, B, C and D - belong to an island, in which each person belongs to one of the three tribes - Truth tellers, Alternators and Liars. Truth tellers always tell the truth, Alternators alternate between true and false statements, in any order and Liars always lie. A, B, C and D earn their respective livelihoods as a Banker, a Journalist, an Engineer and a Doctor, not necessarily in the same order. When asked about the tribes and how they earn their livelihoods, each of them made exactly three statements. B made his first and third statements in the local language, which was incomprehensible, but made his second statement in English. However, A, C and D made all their statements in English.A:Statement 1: B’s first statement is that, “C is either a Journalist or a Doctor.”Statement 2: C is not a Truth teller.Statement 3: B is an Engineer.B:Statement 1: Aabra ka Daabra.Statement 2: Atleast one of my statements is false.Statement 3: Daan a kun.C:Statement 1: A is a Doctor.Statement 2: B’s third statement is that, “D is a truth teller.”Statement 3: D is neither a Journalist nor an Engineer.D:Statement 1: C made exactly one true statement.Statement 2: Exactly two of us are truth tellers.Statement 3: C is a Journalist.Among A, B, C and D, at least one person of each tribe is present.Q. Who is the Banker?a)Ab)Bc)Cd)De)Cannot be determinedCorrect answer is option 'D'. Can you explain this answer? has been provided alongside types of Four friends - A, B, C and D - belong to an island, in which each person belongs to one of the three tribes - Truth tellers, Alternators and Liars. 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However, A, C and D made all their statements in English.A:Statement 1: B’s first statement is that, “C is either a Journalist or a Doctor.”Statement 2: C is not a Truth teller.Statement 3: B is an Engineer.B:Statement 1: Aabra ka Daabra.Statement 2: Atleast one of my statements is false.Statement 3: Daan a kun.C:Statement 1: A is a Doctor.Statement 2: B’s third statement is that, “D is a truth teller.”Statement 3: D is neither a Journalist nor an Engineer.D:Statement 1: C made exactly one true statement.Statement 2: Exactly two of us are truth tellers.Statement 3: C is a Journalist.Among A, B, C and D, at least one person of each tribe is present.Q. Who is the Banker?a)Ab)Bc)Cd)De)Cannot be determinedCorrect answer is option 'D'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice Four friends - A, B, C and D - belong to an island, in which each person belongs to one of the three tribes - Truth tellers, Alternators and Liars. Truth tellers always tell the truth, Alternators alternate between true and false statements, in any order and Liars always lie. A, B, C and D earn their respective livelihoods as a Banker, a Journalist, an Engineer and a Doctor, not necessarily in the same order. When asked about the tribes and how they earn their livelihoods, each of them made exactly three statements. B made his first and third statements in the local language, which was incomprehensible, but made his second statement in English. However, A, C and D made all their statements in English.A:Statement 1: B’s first statement is that, “C is either a Journalist or a Doctor.”Statement 2: C is not a Truth teller.Statement 3: B is an Engineer.B:Statement 1: Aabra ka Daabra.Statement 2: Atleast one of my statements is false.Statement 3: Daan a kun.C:Statement 1: A is a Doctor.Statement 2: B’s third statement is that, “D is a truth teller.”Statement 3: D is neither a Journalist nor an Engineer.D:Statement 1: C made exactly one true statement.Statement 2: Exactly two of us are truth tellers.Statement 3: C is a Journalist.Among A, B, C and D, at least one person of each tribe is present.Q. Who is the Banker?a)Ab)Bc)Cd)De)Cannot be determinedCorrect answer is option 'D'. Can you explain this answer? tests, examples and also practice UPSC tests.
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