8целых1/3-5=25/3-5/1=25/3-5/3=25/3-15/3=10/3
8целых1/3+5/6=25/3+5/6=25/6+5/6=50/6+5/6=55/6
7целых1/5-1/15=36/5-1/15=36/15-1/15=108/15-1/15=107/15
7целых2/7-4целых3/14=51/7-56/14=51/14-56/14=102/14-56/14=46/14
8-1целая3/5=8/1-8/5=8/5-8/5=40/5-8/5=32/5=6,4.
9целых1/20-5целых17/30=181/20-167/30=181/60-167/60=543/60-334/60=209/60=3,49.