5 7/15-(7 1/12-(4 29/60-(2 1/5-1 5/6)))

57:15-(71:12-(429:60-(21:5-15:6)))=57:15-(71:12-(429:60-(4,2-2,5)))=57:15-(71:12-(429:60-1,7))=57:15-(71:12-(7,15-1,7))=57:15-(71:12-5,45)=57:15-(5,92-5,45))=57:15-0,47=3,8-0,47=3,33