Elaine Hou, a Seffner resident and sophomore at King High School, won a bronze medal last week at the 10th annual China Girls Math Olympiad, an international math competition held in Shenzhen, near Hong Kong. Hou was one of eight high school girls on the U.S. team who won medals in the competition, which included nearly 200 girls from Japan, Russia, the Philippines, China and other countries. Teams completed a rigorous two-day exam Aug. 1 and 2, challenging them to solve difficult math problems. The Mathematical Sciences Research Institute sponsored the U.S. team for a fifth year. Team members were selected from the top ranks of female finalists in the 2011 USA Mathematical Olympiad.