Japanese teacher gets poor marks for deadly maths exercise

BEIJING - A Japanese primary-school teacher got into trouble after asking his students to calculate how many days it would take to kill 18 children if you murdered three each day, a news report said Wednesday.

The education authority in Aichi prefecture let the 45-year-old teacher in the city of Okazaki off with a warning, the Kyodo News agency reported.

The teacher said the maths question simply slipped out and promised it would not happen again.

The authority said it would keep an eye on him in future.