3 1/3 : k = 1 1/3 : 2
3 1/3:k=1 1/3:2 3 1/3:k=1/2+1/6 3 1/3:k=3/6+1/6 3 1/3:k=4/6 k=3 1/3:4/6 k=20/6:4/6 k=5/6