Write a paraphrased version of the paragraph.
Around 510 000 pupils aged from 15 years 3 months to 16 years and 2 months took part in the tests, which covered maths, reading and science, with the main focus on maths.
The math, science and reading tests, with a key focus on mathematics, were carried out by approximately 510,000 pupils aged between 15 and 3 and 16, 2 months.