About Abu Bakr al-Hassar
Abu Bakr al-Hassar was a Moroccan mathematician and writer.
Al-Hassar or Abu Bakr Muhammad ibn Abdallah ibn Ayyash al-Hassar was a 12th-century Moroccan mathematician. He is the author of two books Kitab al-bayan wat-tadhkar (Book of Demonstration and Memorization), a manual of calculation and Kitab al-kamil fi sinaat al-adad (Complete Book on the Art of Numbers), on the breakdown of numbers. The first book is lost and only a part of the second book remains.
Al-Hassar developed the modern symbolic mathematical notation for fractions, where the numerator and denominator are separated by a horizontal bar. This same fractional notation appeared soon after in the work of Fibonacci in the 13th century.
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Who was Abu Bakr al-Hassar?
Moroccan mathematician
What was Abu Bakr al-Hassar's occupation?
Abu Bakr al-Hassar was a mathematician and writer.
What nationality was Abu Bakr al-Hassar?
Abu Bakr al-Hassar was Moroccan.
Sources & further reading
· Wikipedia: Abu Bakr al-Hassar
· DBpedia: Abu Bakr al-Hassar
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APA: Biography.guide. (2026). Abu Bakr al-Hassar. https://biography.guide/abu-bakr-al-hassar/
MLA: "Abu Bakr al-Hassar." Biography.guide, https://biography.guide/abu-bakr-al-hassar/.
Chicago: "Abu Bakr al-Hassar." Biography.guide. https://biography.guide/abu-bakr-al-hassar/.
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