2/3-0,25 11/25+4/10 7/34+1/17

1) 2/3-0,25 = 2/3-1/4 = (8-3)/12 = 5/122) 11/25+4/10 = (22+20)/50 = 42/50 = 0,843) 7/34+1/17 = (7+2)/34 = 9/34