May 15, 16 Mei, May 19
June 17, 18 Juni
July 14, 16 July
August 14, 15 August and August 17
Cheryl gave some clue abaut the date of the birthday to Albert and Bernard separately on the anniversary date of the month, in different occasions.
Albert and Bernard then made the statement:
Albert: I do not know when Cheryl's birthday, but I'm sure Bernard did not know well.
Bernard: At first I did not know Cheryl's birthday, but I now know.
Albert: It means I also know Cheryl's birthday.
So, when Cheryl's birthday?
Dare to try?