Arabic mathematicians extended the system to include decimal fractions, and Muḥammad ibn Mūsā al-Ḵwārizmī wrote an important work about it in the 9th  century.
Kal maɗinan ən araban asewaɗan əmik fal adigišan fraətiontan ən déəimal, əd Muhammad ibn Mūsā al-Kwārizmī əktab alkitab iknan ye salan wən 9e temede nawatay.