Symmetry wrote:Albert and Bernard just became friends with Cheryl, and they want to know when her birthday is.
Cheryl gives them a list of 10 possible dates. May 15, May 16, May 19, June 17, June 18, July 14, July 16, August 14, August 15, August 17. Cheryl then tells Albert and Bernard separately the month and the day of her birthday respectively.
Albert says: “I don’t know when Cheryl’s birthday is, but I know that Bernard does not know too.”
Bernard says: “At first I don’t know when Cheryl’s birthday is, but I know now.”
Albert says: “Then I also know when Cheryl’s birthday is.”
So when is Cheryl’s birthday?
ok so i'll try without looking at others
albert -> knows month
bernanrd -> knows day
Albert can't determine it alone, but he gives a hint that gives bernard the answer. "I know that Bernard does not know too.”
14th -> 2 dates
15th -> 2 dates
16th -> 2 dates
17th -> 2 dates
18th -> 1 date
19th -> 1 date
-> the only way for bernard to know first hand, would be if it was the 18th or 19th. So it is not.
-> so that gave a hint big enough for bernanrd to now determine the birthday.. If it's the case, it has to be a month where he has 1/1 chances after removing the 18 and 19.
The 19 is in may with 3 dates, so it's june that has only 2 dates including the 18th.
That bitche's birthday is on June 17th, and she's extremely rude.
