Japanese teacher in trouble for "deadly" maths question

A maths teacher in Japan received a stern talking to from the authorities after he posited the following question to his primary school students: how many days it would take to kill 18 children if you murdered three each day? The teacher's been let off with a warning from the education authority of the Aichi prefecture, and a promise that he'd be watched. For his part, the teacher said it would never happen again. The answer is six days, in case you're wondering. Read more: Sapa-DPA, via IOL