In maths, 35% of the 2,000 adults who took part in the YouGov survey said they would no longer know how to calculate the mode, 31% the median, 28% the mean and 27% the area of a circle.

Respondents were challenged by long division and multiplication, with a quarter unable to remember how to do the former and 23% the latter. Meanwhile, 26% had forgotten how to work out the square root.

In English, many showed a similarly shaky grasp of punctuation with almost one in four admitting to not knowing when to use a semi-colon (23%); 18% the rules governing the use of an apostrophe; and 17% when to use a comma.