# When is Cheryl's birthday?

Level pending

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.

$\begin{eqnarray*} May 15 &&&&& May 16 &&&&& May 19\\ June 17 &&&&& June 18 &&&&& \\ July14 &&&&& July 16 &&&&& \\ August 15 &&&&& August 15 &&&&& August 17 \end{eqnarray*}$

Cheryl then tells Albert and Bernard separately the month and the day of her birthday, respectively.

Albert: I don't know when Cheryl's birthday is, but I know that Bernard does not know, too.

Bernard: At first, I didn't know when Cheryl's birthday is, but I know now.

Albert: Then I also know when Cheryl's birthday is.

So when is Cheryl's birthday?

×