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Cheryl's Birthday

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CAN YOU CRACK THIS MATHS OLYMPIAD QUESTION? JUST RE POSTING IT!

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?

  • 2 weeks later...
On 15.01.2018 at 10:58 AM, Spiri.Of.Genius said:

So when is Cheryl's birthday?

17 June

 

Albert got June,

Bernard got 17.

(if Bernard would get 18 or 19, he would know exact day without having to know month, as they're unique)

  • 3 weeks later...

Jun 18

On 2018. 01. 24. at 8:09 PM, Sensei said:

(if Bernard would get 18 or 19, he would know exact day without having to know month, as they're unique)

right.

  • 1 month later...

A third person can deduce it must be July 16 using all three clues.

Edited by TakenItSeriously

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