Perhaps you heard about the math problem from a Singapore high school Olympiad exam that is stumping people on the internet-lah.
Ah gong was acting like a ya ya papaya, pretending that to a Singapore third grader, the problem was easy. Kpkb, Kao pei la, but it is actually a very difficult question that comes at the end of a very difficult SASMO Asian Math Olympiad examination in Singapore-lah.
In the math question, Cheryl meets two boys: Albert and Bernard. They ask her for her birthdate. She answers with ten possible dates. She then tells (A)lbert the month of her birthdate, and (B)ernard the day of her birthday.
The dates are:
May 15 May 16 May 19
June 17 Jun 18
July 14 July 16
Aug 14 Aug 15 Aug 17
The math problem continues:
(A)lbert: I don’t know Cheryl’s birthdate, but I know that (B)ernard does not know either
(B)ernard: At first, I didn;t know Cheryl’s birthdate, but I now know.
(A)lbert: And now I know as well.
* * *
In my opinion, they are all not Jewish.
Why did Albert and Bernard ask Cheryl her birthday as soon as they met?
And what is Cheryl’s problem. What kind a nut gives her answer as a riddle?
Is this the kind of person you want to have a friend?
I think this is what would happen if they were Jewish:
Avi and Bibi meet Chaya.
They don’t give a damn about her birthday, but they do ask if she lives on the Upper West Side, what she pays in rent, and which shul she attends.
She answers them directly, and offers no riddle.
They invite her over for shabbos.
End of math problem
SPOILER: HOW TO SOLVE IT
Albert knows the day. There is only one ’19’ and one ’18.’ They can be eliminated
We can also eliminate May and June
We are left with July 14 July 16 and Aug 14 and Aug 15 and Aug 17
Since Bernard figured it out, we know that it can’t be ’14’ since there are two of them
We are left with July 16, Aug 15, and Aug 17
But Albert only knows the month. He says he knows. There is only one date in July. So the answer is July 16.