Multiple choice general knowledge math & puzzles

A: I am older than B B: I am younger than A C: I am younger than A and B One among A,B and C is telling the truth. The other two are telling lies. Who is telling the truth?

  1. A

  2. B

  3. C

  4. Data Insufficient
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

If only C tells the truth (C is younger than A and B), then A and B lie. A claims to be older than B, but since A lies, A is actually younger than or equal to B. B claims to be younger than A, but since B lies, B is actually older than or equal to A. Combining 'B is not younger than A' and 'A is not older than B' gives A = B. With C truly being younger than both, the age order is A = B > C, which is consistent.

AI explanation

Notice A's statement ("I am older than B") and B's statement ("I am younger than A") describe the exact same relationship, so they must always share the same truth value. Since only one statement overall can be true, A and B's statements must both be false (meaning B is not younger, i.e., B is older than or equal to A), which forces C's statement — being younger than both A and B — to be the true one, making C the truth-teller.

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