7/15-1/6-1/10=14/30-5/30-3/30=6/30=1/5
9/10-7/15+4/45=27/30-14/30+4/45=13/30+4/45=39/90+8/90=47/90
х+1/8=5/8-1/7
х=5/8-1/7-1/8=4/8-1/7=28/56-8/56=20/56
7/15-1/6-1/10=14/30-5/30-3/30=6/30=1/5
9/10-7/15+4/45=27/30-14/30+4/45=13/30+4/45=39/90+8/90=47/90
х+1/8=5/8-1/7
х=5/8-1/7-1/8=4/8-1/7=28/56-8/56=20/56