How much do you recall from your schooldays?
Despite all those years we spent in school, some of us would struggle to recall lots of what we learnt.
At least that seems to be the case if the latest riddle to have people scratching their heads is anything to go by.
This maths question was given to seven-year-old students as part of their homework, and it left lots of people on social media stumped.
Dad-of-two – Dr Kit Yates, author of the book The Maths Of Life And Death and co-director of the Centre for Mathematical Biology at Bath University – shared the baffling question on his Twitter feed.
He asked: “This was my daughter’s (7) maths homework on Monday. Can someone help me out with the answer?”
He added: “I’m not being facetious here. I’m genuinely not sure what I should advise her the correct answer should be.”
The image shows a semi-circle in a box with the question: “True or false? This shape has two right angles. Explain your answer.”
The math’s lecturer’s question went viral – as lots of people admitted they were stumped.
One person joked: “Someday I’d like to teach an undergraduate class titled “Central Questions in Philosophy” where the only course text is third-grade math problems.”
Another suggested: “I’m going for yes, on the basis that in as much as a single angle exists for a curved line it should be 90 degrees at those two points. (ie there’s no other single value that makes sense).”
A third helpfully contradicted that answer, as they replied: “I’d say no because there are curved lines but maybe I’m wrong. That seems damn tough for someone so young.”
The lecturer agreed that the question was tough – as he told The Mirror – and said he would set the question for his university students next week.
He said: “I am in a fortunate position that meant I felt I could be used this as an opportunity to talk to my daughter about how the answer could be either true or false depending on your understanding of ‘angle’.
“But I’m sure not every parent, or teacher for that matter, would have the time to delve too far into this.
“It’s actually a really deep and thought-provoking question which could be used later on in school to spark conversations about infinity, tangents, calculus and many more interesting mathematical concepts, but it might not be best for seven-year-olds being homeschooled by their parents!
“I’m going to set it as a riddle for my second year University Maths students next week to see what they come up with.”
If you’re desperate to know, according to an answer sheet found online, the answer is “false.” It explains that children could show this by using the corner of a page to show that there aren’t any right angles.”
In case you weren’t finding it tough enough already, Dr Yates explains that there is a strong argument for saying the answer is “True.”
He said: “As a mathematician though I am aware that we can also think about the angle between two curved lines as the angle
that their tangents (the straight lines parallel to the curve at that
point) would make.
“If you “zoom in” then sure enough the tangents to the semicircle do meet its diameter at right angles. So there’s definitely a
strong argument for putting “True” down as the answer.