May 27 (Reuters) - A majority of FirstGroup shareholders on Thursday backed the British company’s planned 3.3 billion pound sale of its two U.S. bus assets to EQT Infrastructure, in a blow to activist investor Coast Capital which led a rebellion against the deal. The public transport operator said 61.3% of votes cast at the shareholder meeting were in favour of the proposed sale of FirstStudent and FirstTransit to the Swedish private equity fund. The sale needed the support of at least half of all votes cast to go through. Reporting by Yadarisa Shabong in Bengaluru; Editing by Krishna Chandra Eluri Our Standards: The Thomson Reuters Trust Principles.