Image copyright iStock Image caption The question has gone viral online

An apparently unsolvable exam question on a Chinese maths paper has left both students and social media stumped.

Primary school students at a school in the Chinese district of Shunqing were faced with this question on a paper: "If a ship had 26 sheep and 10 goats onboard, how old is the ship's captain?"

The question appeared on a recent fifth-grade level paper, intended for children around 11 years old.

Pictures of the question, along with students' valiant attempts at answers, surfaced this week on Chinese social media - where it triggered debate and quickly went viral.

Education officials later said the question was not a mistake, but meant to highlight "critical awareness".

Image copyright Weibo Image caption It is not clear how many points the question (circled) was worth or if it was part of a bonus section

"The captain is at least 18 because he has to be an adult to drive the ship," one student answered.

"The captain is 36, because 26+10 is 36 and the captain wanted them to add up to his age," another guessed.

One student however, simply gave up.

"The captain's age is... I don't know. I can't solve this."

Online, however, people weren't quite as generous.

"This question makes no logical sense at all. Does the teacher even know the answer?" said one commenter on Weibo, a Chinese microblogging platform.

"If a school had 26 teachers, 10 of which weren't thinking, how old is the principal?" another asked.

Some however, defended the school - which has not been named - saying the question promoted critical thinking.

"The whole point of it is to make the students think. It's done that," one person commented.

"This question forces children to explain their thinking and gives them space to be creative. We should have more questions like this," another said.

'Think outside the box'

The Shunqing Education Department posted a statement on the 26 January saying the test had intended to "examine... critical awareness and an ability to think independently".

"Some surveys show that primary school students in our country lack a sense of critical awareness in regard to mathematics," it said.

The traditional Chinese method of education heavily emphasises on note-taking and repetition, known as rote learning, which critics say hinders creative thinking.

But the department said questions like the boat one "enable students to challenge boundaries and think out of the box".

And of course, there's always that one person that has all the answers.

"The total weight of 26 sheep and 10 goat is 7,700kg, based on the average weight of each animal," said one Weibo commenter.

"In China, if you're driving a ship that has more than 5,000kg of cargo you need to have possessed a boat license for five years. The minimum age for getting a boat's license is 23, so he's at least 28."