Even if students left out those questions altogether, he added, they would still be able to achieve an A or B grade.

Students took to social media to complain that the Edexcel C1 maths paper required them to multiply complex fractions in their heads. The questions did not include any whole numbers, which are quicker and easier to multiply and divide without a calculator.

This is not the first controversy of exam season. Yesterday, pupils took to the internet to vent their fury over an AQA GCSE biology paper, intended to cover the study of living organisms, which asked pupils what was meant by the term “independent company”. The question referred to a drugs-trial firm.

And almost 25,000 Scottish pupils have signed a petition claiming that their N5 mental-arithmetic exam - the equivalent of a GCSE - was unusually hard. They called for the pass mark to be reduced, or for the results of continuous assessments through the year to be taken into account in their final grade.

However, maths teachers are unconvinced that the Edexcel outcry amounts to anything more than a good, old-fashioned post-exam rant.

One Oxfordshire head of maths said: “I didn’t look at the paper and think, ‘Oh, my God. What was this? We should complain to the exam board.’

“There are a couple of questions that are really tricky, but I would guess that you can still get an A or B grade, missing out those bits. Past papers absolutely did prepare them for this.

“Students come out of exams, and some of them say ‘It’s fine’, and some of them say ‘It was really bad’. That’s just exams.”

This was echoed by a spokesperson from Edexcel, who said: “The paper was a reflection of the curriculum that students have studied this year. With every paper there there will always be questions that some students find difficult, which is often reflected in social-media comment.”

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