Cheryl's birthday:A Math Problem From Singapore Goes Viral

Hi friends,

This amazing question gone viral recently.

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

Bernard: At first I don'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?

Try to solve by your own logic & post the solution and try to not cheat

Note by Ayush Verma
6 years, 2 months ago

1 vote

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Comments

I have posted this problem here. Let's keep the solution discussions on that problem.

I have locked this note.

Calvin Lin Staff - 6 years, 2 months ago
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