1)5-14/15 = 4 1/15 = 61/15
2)11/15 + 0,3 = 11/15 + 3/10 = 22/30+9/30 = 31/30
3)61/15:31/30 = 61/15*30/31 = 61*2/31 = 122/31 = 3 29/31
42/100=21/50
56/63=8/9
81/60=27/20=1 целая 7/20
72/420=12/70=6/35
75/74=1целая 1/74
35/25=7/5=1 целая 2/5
36/42=6/7
42/32=21/16=1 целая 5/16