Convert from arratel, artel [Arab] to quintal [metric]

Unit Definition (arratel, artel [Arab])
The arratel is a versions of a traditional Arab unit of weight; see rotl. The spelling "arratel" is used in Portugal as an alternate name for the libra.

Unit Definition (quintal [metric])
The quintal [metric] is a common metric unit of mass equal to 100 kilograms or approximately 220.4623 pounds. Notice that the metric ton is roughly equal to its non-metric predecessors, but the metric quintal is about twice the size of the traditional quintal.