Nearly half of the UK's working-age population have the numeracy skills of a primary school pupil, according to the organisers of National Numeracy Day (16 May), who are hoping to improve attitudes towards maths.
You can give your own mental arithmetic skills a challenge by taking our maths quiz below, compiled using questions from the government's numeracy professional skills test.
All prospective teachers must pass the test before becoming qualified, no matter their specialist subject.
To take the test properly, you should read and answer each question within 55 seconds, without the help of a calculator.
Remember to read each question carefully.
Main image: Shutterstock