Can you answer the latest maths question confusing some adults?
A baffled father posted the puzzle aimed at ten-year-olds on Facebook claiming it was 'impossible' to answer, however others claim they answered it in seconds.
The question asks students to calculate the perimeter of two rectilinear shapes, the first has two sides labelled 12cm and 10cm.
The 43-year-old, who has A-levels in maths and economics, said the question was a homework assignment given to his son who attends a school in Glossop, Derbyshire, the Manchester Evening News reports.
He explained that both he and the boy's grandmother could not answer the question, adding that a friend with an economics degree was also left confused.
"My son's grandma had spent a while helping him with his homework and most of it was straightforward but this one question left her stumped," he wrote.
"I then spent an hour or so trying to work it out but found it impossible.
"I even sent it to a friend who got a 1st class degree in economics and they were baffled by it as well."
He added: "A couple of friends are maths teachers too so I've sent it to them but so far I've heard nothing back.
"I really do think it is impossible and it is certainly not something a ten-year-old can answer.
"It just does not make sense."
It's not the first exam question to divide the internet. Here's why 5+5+5 doesn't always make 15.
While here's what happened when a professor tested students' ethics with a cruel exam question.
Another exam question aimed at seven-year-olds has also divided internet users. Can you answer it?
The Telegraph, London