Вычислите сумму:2/51+4/17; 4/65+6/13+1/5; 5/9+3/20; 1/12+2/6+3/48
2/51 + 4/17 = 6/68 4/65 + 6/13 + 1/5 = 11/83 5/9 + 3/20 = 8/29 1/12 + 2/6 + 3/48 = 6/66