The question was intended for students in fifth-grade – around 11 years old.
Pictures of the question and students’ attempts to answer it have gone viral on Chinese social media and triggered debate among netizens.
The Shunqing Education Department posted a statement saying the test was not a mistake and had intended to “examine… critical awareness and an ability to think independently”, reported the BBC.
“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 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".
"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."
Some netizens have questioned whether teachers know the answer, while others have defended the school.
"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.
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