In the Arabic language, all sentences are starts from right to left direction.. But when we write any number, why we are not following the same?

Historians trace modern numerals in most languages to the Brahmi numerals, which were in use around the middle of the3rd century BC. The place value system, however, evolved later. The Brahmi numerals have been found in inscriptions in caves and on coins in regions near Pune, Mumbai, and Uttar Pradesh. These numerals (with slight variations) were in use over quite a long time span up to the4th century.During the Gupta period (early4th century to the late6th century), the Gupta numerals developed from the Brahmi numerals and were spread over large areas by the Gupta empire as they conquered territory. Beginning around7th century, the Gupta numerals evolved into the Nagari numerals.Before the rise of the Arab Empire, the Hindu-Arabic numeral system was already moving West and was mentioned in Syria in662 AD by the Nestorian scholar Severus Sebokht who wrote the following:  "I will omit all discussion of the science of the Indians, ... , of their subtle discoveries in astronomy, discoveries that are more ingenious than those of the Greeks and the Babylonians, and of their valuable methods of calculation which surpass description. I wish only to say that this computation is done by means of nine signs. If those who believe, because they speak Greek, that they have arrived at the limits of science, would read the Indian texts, they would be convinced, even if a little late in the day, that there are others who know something of value."According to al-Qifti's chronology of the scholars :    "... a person from India presented himself before the Caliph al-Mansur in the year [776 AD] who was well versed in the siddhanta method of calculation related to the movement of the heavenly bodies, and having ways of calculating equations based on the half-chord [essentially the sine] calculated in half-degrees ... This is all contained in a work ... from which he claimed to have taken the half-chord calculated for one minute. Al-Mansur ordered this book to be translated into Arabic, and a work to be written, based on the translation, to give the Arabs a solid base for calculating the movements of the planets ..."The work was most likely to have been Brahmagupta's Brahmasphutasiddhanta (Ifrah) (The Opening of the Universe) which was written in628 . Irrespective of whether Ifrah is right, since all Indian texts after Aryabhata's Aryabhatiya used the Indian number system, certainly from this time the Arabs had a translation of a text written in the Indian number system.

Hi, thanks for inviting me........because numbers orginally are not arabian in the first place ...they are indians and probably the indians used to use them like that....also the indians numbers are arabians...but i dont know why that swap happened...i hope that my answer was fulfilling