Convert from qintar [Arab] to arroba [Spain]

Unit Definition (qintar [Arab])
The qintar is a traditional Arabic unit of weight, often called the cantar in English. The qintar is the Arabic counterpart of the European quintal. The unit varied in size from market to market and over time. In recent years, the qintar has been interpreted as an informal metric unit equal to 50 kilograms (110.23 pounds); traditional qintars tended to be a few percent larger than this. The qintar is equal to 100 rotls.

Unit Definition (arroba [Spain])
The arroba [Spain] is a traditional unit of weight in Spain and Portugal, equal to 1/4 quintal. However, the Spanish and Portuguese quintals are of different sizes. In Spain, the arroba equals 25.36 pounds (11.50 kilograms); arrobas of very similar sizes were established in the Spanish speaking countries of Latin America. The arroba has also been used as a metric unit equal to exactly 15 kilograms. The name of the unit comes from ar rub', Arabic for "the quarter."