At the Northside assembly plant, 28% of the workers were classified as minority, while at the Southside assembly plant, 70% of the workers were classified as minority. When Northside and Southside were closed, all workers transferred to the new Eastside plant to make up its entire work force. If 50% of the 2100 employees at Eastside are minority, then how many employees did Northside and Southside have originally