50 is an Arabic numeral and its Roman equivalent is L
It's already an Arabic numeral
The Roman numeral of CCLI is equivalent to the Arabic numeral of 251
Exactly as it is 27 which is an Hindu-Arabic numeral and as a Roman numeral it is XXVII
The Arabic numeral eqivelent of 1776 is 1776. the Roman numeral for 1776 is MDCCLXXVI.
The Roman numeral of CCCL is equivalent to the Arabic numeral of 350
It is the Hindu-Arabic numeral system.
The equivalent Roman numeral of L as an Hidu-Arabic numeral is 50
The Roman numeral of CCLXII is equivalent to the Hindu-Arabic numeral of 262
The Roman numeral of CCLX is equivalent to the Hindu-Arabic numeral of 260
For the same reasons that we need a numeracy system today which is based on the Hindu-Arabic numeral system that was a lot easier than the Roman numeral system that it replaced.