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100 sats \ 4 replies \ @Undisciplined 2 Apr \ on: [Not-so-daily puzzle] Singapore at it, again science
June 17th
If it were June 18th, then Albert would have already known. Bernard, knowing it's June and knowing it's not the 18th, knows it must be the 17th.
Bernard knowing the date, tells Albert that it's not August, so it must be June.
How would Albert know if he only knows the month and not the day?
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If Albert knows it's one of the 17th's then it's either June or August. If it were August, then Albert not knowing wouldn't be enough information for Bernard to deduce anything, because it could be any of the August dates.
Albert not knowing only eliminates the 18th and 19th as possible days, since they're the only ones unique to a month.
Eliminating the 19th would still leave two possibilities for May, so Albert knows it's not May.
The fact that Bernard can infer the answer means the date is from the month reduced to one option.
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Ok, now my turn.
In the Albert eyes:
May 33% possibility Bernard knows the answers (because of unique 19)
June 50% Bernard knows (because of unique 18)
July 0% (there's no unique numbers)
August 0% (no unique numbers).
If Alberts says: Bernard doesn't know answer (read 0% chance) we need months without unique numbers.
Everything else you can follow in my first comment below
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Lol, I mixed up who knows what.
So, they can cross off May and June. But, then if Bernard knows it's a 14th, he still wouldn't know which month.
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