Решите пропорцию 2 5/7х:2 8/9=4 2/13:1 9/19

Решение  

4 5/7х:2 1/13=2 8/9:3 3/11

4(5/7)x * 3(3/11) = 2(1/13) * 2(8/9)

(33*36)*x ]/ (7*33) = [(27*26)/(13*9)]

(36/7)*x = 6

x = 6 : (36/7)

x = 7/6

x = 1(1/6)