а)25/28-18/35=53/140
б)40/63-35/72=25/168
в)22/21-21/22=43/462
г)140/143-41/156=1229/1716
д)43/126-41/135=71/1890
е)239/240-229/288=289/1440
б) 40/63-35/72 =(40*72-35*63)/(63*72)=675/4536
в) 22/21-21/22 =(22*22-21*21)/(21*22)=43/462
а)25/28-18/35=53/140
б)40/63-35/72=25/168
в)22/21-21/22=43/462
г)140/143-41/156=1229/1716
д)43/126-41/135=71/1890
е)239/240-229/288=289/1440