An article costing C dollars is sold for $100 at a lostt of x percent of the selling price. It is then resold at a profit of x percent of the new selling price S′. If the difference between S′ and C is 191 dollars, then x is:
<spanclass=′latex−bold′>(A)</span>undetermined<spanclass=′latex−bold′>(B)</span>980<spanclass=′latex−bold′>(C)</span>10<spanclass=′latex−bold′>(D)</span>995<spanclass=′latex−bold′>(E)</span>9100