Dr Joseph Yeo Boon Wooi, a mathematics professor at Singapore
SINGAPORE: The man behind the "Cheryl's birthday" viral poser is a mathematics professor from Singapore's National Institute of Education (NIE).
Dr Joseph Yeo Boon Wooi, who is in his 40s, is part of the panel for the Singapore and Asian Schools Math Olympiads (Sasmo), the largest math competition in the country.
