Update from @MOEsg: *"Hi all, we wish to clarify that the supposed PSLE math question on figuring out Mr Tan’s birth date is not a PSLE question."*

Supposedly a PSLE maths question. My brain just had cramps.

If you want the answer, click below to see it after the page break.

This is apparently the answer to the maths question in the maths problem above. Now my brain really has a Charlie Horse.

Update: Mr Lee Chee Wai, a friend of a friend, seems to have solved the question too. But he also has a Phd or something…

*Sequence of elimination:
1. N = {1, 2x, 4, 5, 7x, 8 }, M = { 3, 6x, 9, 12x }
2. N = {1, 4, 5x, 8}, M = { 3, 9}
3. N = {1, 4, 8}, M = {3x, 9}*

Final answer has to be N=1, M=9.

*1. "I know you don't know" - translation: The N values given my value of M have no unique values. Effect: Eliminates the appropriate N and M values from consideration.
2. "Ah, now I know." - translation: My value of N must have a unique value of M. Effect: the elimination of the value of N=5.
3. "Oh, now I also know." - translation: My value of M can only have one unique value of N given the possibilities that remain. Effect: M=3 is eliminated.*

In other news, this question was seen on Facebook:

"Is Hong Lim Park a Korean actor?"

The brother of this Korean star Hong Lim Park must be Pung Gol Park.