If not, a sequence of tests using a type of mathematics called modular arithmetic is carried out.

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In the new single level tests being piloted in English reading, English writing and mathematics, the questions are all pitched at a certain level of understanding.

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The 150, 000 applicants each year must first pass exams in chemistry, physics and mathematics before they can sit for a second set of grueling analytical tests.

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The OECD Programme for International Student Assessment or Pisa tests examines the performance of 15-year-old pupils in mathematics, science, and reading.

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