'Cheryl's birthday' poser is back with Part 2: Cheryl's age

The second part to the viral "Cheryl's birthday" puzzle: Can you find out Cheryl's age? -- PHOTO: NANYANG TECHNOLOGICAL UNIVERSITY/FACEBOOK
The second part to the viral "Cheryl's birthday" puzzle: Can you find out Cheryl's age? -- PHOTO: NANYANG TECHNOLOGICAL UNIVERSITY/FACEBOOK

SINGAPORE - First it was her birthday. This time, Cheryl's age is up in the air with a second part to the viral puzzle that made international headlines recently.

Nanyang Technological University (NTU) posted the question, which challenges people to work out Cheryl's age, on their Facebook page on Thursday night.

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It also urged readers to grab a copy of its bi-monthly magazine, HEY!, to read more about Dr Joseph Yeo, the mathematics lecturer from the National Institute of Education who had set the now famous question as part of the Singapore and Asian Schools Math Olympiads (SASMO).

In an interview with The Straits Times last month, Dr Yeo shared that "Cheryl's birthday" was not a new logic problem and he had modified it by changing the names, date and context.

The question, which was leaked and made its way onto Facebook on April 12, generated a global buzz and was covered by media such as The New York Times, the BBC and the Guardian.

mklee@sph.com.sg

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