78/1+6/13= прошшууууу
78/1 = 78 : 1 = 78 целых. 78 + 6/13 = 78 целых 6/13
ужас
78/1 + 6/13 =(78 × 13 + 6 × 1)/13 = 1014/13 + 6/13 = 1020/13 = 78 6/13