BRASILIA, April 24 : Brazil has blocked prediction market platforms and tightened derivatives rules to curb "bet-like" products, Finance Minister Dario Durigan said on Friday, arguing such markets breach betting regulations approved by Congress. Speaking at a press conference, Durigan said 28 prediction market platforms had been shut down in Latin America's largest economy by telecoms regulator Anatel. Hours later, the Finance Ministry revised the figure to 27 firms. Websites of companies such