"The kid starts cackling, and I realise he invented his own question in order to trick me into saying it," the teacher wrote.

Are you a maths whizz? Can you even best a 14-year-old with your numeracy skills without counting on your fingers? We are again asking MailOnline readers if their mathematical skills are up to par ...

If there's one subject a lot of people really disliked at school (aside from P.E.) it was maths. Trying to work out all those equations, fractions and percentages gave me a stonking headache and I'm ...