K - 4/9k + 1/6k при k=2 10/13
k - 4/9k + 1/6k = 18/18k - 8/18k + 3/18k = 13/18k
при k = 2 целых 10/13 = (2·13+10)/13 = 36/13
13/18k = 13/18 · 36/13 = 36/18 = 2
Ответ: 2.