870
а.)х+1/8=3/5
х=3/5-1/8=24/40-5/40
х=19/40
б.)1/3+х=5/12
х=5/12-1/3=5/12-4/12
х=1/12
в.)х-3/20=1/5
х=1/5+3/20=4/20+3/20
х=7/20
г.)х-3/7=4/21
х=3/7+4/21=9/21+4/21
х=13/21
д.)4/5-х=1/6
х=4/5-1/6=24/30-5/30
х=19/30
е.)5/8-х=1/3
х=5/8-1/3=15/24-8/24
х=7/24
872
а.)25/28-18/35=125/140-72/140=53/140
б.)40/63-35/72=320/504-245/504=75/504=25/168
в.)22/21-21/22=484/462-441/462=43/462
г.)40/143-41/156=480/1716-451/1716=29/1716
д.)43/126-41/135=645/1890-574/1890=71/1890
е.)239/240-229/288=1434/1440-1145/1440=289/1440