Problem bank

Problem 104 of 333HardBrainteaserP104

Cheryl's birthday

  1. Albert and Bernard learn the month and day of Cheryl's birthday respectively. Cheryl gives them a list of possible dates. Albert: 'I don't know, but I know Bernard doesn't either.' Bernard: 'I didn't know, but now I do.' Albert: 'Now I know too.' Reasoning?