Right, we'll admit now that we're not very good at maths at the best of times, but we at least thought that we could still tackle the odd problem from 5th class.

However, that doesn't take into account that the schools in Singapore normally come out either on top or very near the top of international rankings for primary ability in mathematics, and this question rather helps to explain that position.

The problem was posted up on TV presenter Kenneth Kong's Facebook page, and got thousands of shares with plenty of people doing their best to work out the problem.

The premise of the logical problem is that Cheryl gives Albert and Bernard 10 different options for the month that she's born in. Albert is told the month that Cheryl is born, and Bernard is told the day. Can you work out when her birthday is? You'll get points for your rough work even if you get the answer wrong. If you really want the answer, then scroll down a bit.

Via The Guardian. Pic via Bill Selak/Flickr

The correct answer is July 16th, and you can get a breakdown of how that works over on the original Facebook post