At least 31 students in Hong Kong have achieved top marks in the International Baccalaureate (IB) programme, even after a global outcry from test-takers over concerns that the mathematics subject was too difficult. More than 2,600 Hong Kong students sat the IB exams on May 15, 16 and 21, a near 20 per cent increase over the past five years, with the results released on Sunday. The IB exams assess students’ knowledge of several core academic subjects and play a key role in their university...