Cheryl's Birthday Puzzle || Brilliant Viral Puzzle on Facebook and WhatsApp

Cheryl's birthday problem has been extrmeley viral on facebook and whatsapp since 2015 till date. Albert and Bernard have just become 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 repsectively. Albert : I don't know when cheryl's birthday is, But i know that Bernard doesn't know either. Bernard : At first I didn't know when cheryl's bithday is, but I know now. Albert : Then I also know when Cheryl's birthday is. So when is cheryl's birthday ? Also check out difficult puzzles and interview riddles on this channel. 10 Prisoners hat puzzle:    • Prisoner Hat PUZZLE || 10 Prisoners || RED...   25 Horses race puzzle:    • Difficult Puzzle || 25 Horses Race || Aske...   Music credit: [No Copyright Music] DRIVE - Nicolai Heidlas Music