第21届中学生国际数学奥林匹克于去年6月22日至7月9日在英国伦敦举行,共有22个国家的代表参加。有一名来自卢森堡的学生还作为比利时代表队的成员参加了竞赛,澳大利亚的代表则以观察员的身分与会(均参加竞赛)。根据传统,每一个国家的代表队由8名中学生和两名领队组成,但有三个国家例外:它们是巴西(由5名中学生组成),越南和古巴(均由4名中学生组成)。这些国家的代表队来英国之前,一般都经过了 The 21st Middle School International Mathematical Olympiad was held in London, England from June 22 to July 9 last year with the participation of 22 countries. One student from Luxembourg also joined the competition as a member of the Belgian team while the Australian delegate attended as an observer (all participating in the competition). Traditionally, each country's national team consists of eight high school students and two team leaders, with the exception of three countries: Brazil (composed of five secondary students), Vietnam and Cuba (each composed of four secondary students). The representatives of these countries have generally passed before coming to Britain