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Logicians Numbers
Two logicians (A and B) each pick a whole number from 1 to 30 inclusive. The following conversation happens:
- A: “Is your number double mine?”
- B: “I don’t know. Is your number double mine?”
- A: “I don’t know. Is your number half mine?”
- B: “I don’t know. Is your number half mine?”
- A: “I don’t know.”
- B: “I know your number.”
All the statements are true. What is A’s number and how did B know?
Solution