1/2 : {1 - 1/2 : [1/5 + 4 x (1/3 + 1/3 : 2)] + 1/11} =
= 1/2 : {1 - 1/2 : [1/5 + 4 x (1/3 + 1/3 x 1/2)] + 1/11} =
= 1/2 : {1 - 1/2 : [1/5 + 4 x (1/3 + 1/6)] + 1/11} =
= 1/2 : {1 - 1/2 : [1/5 + 4 x (2/6 + 1/6)] + 1/11} =
= 1/2 : [1 - 1/2 : (1/5 + 4 x 3/6) + 1/11] =
= 1/2 : [1 - 1/2 : (1/5 + 2) + 1/11] =
= 1/2 : [1 - 1/2 : (1/5 + 10/5) + 1/11] =
= 1/2 : (1 - 1/2 : 11/5 + 1/11) =
= 1/2 : (1 - 1/2 x 5/11 + 1/11) =
= 1/2 : (1 - 5/22 + 1/11) =
= 1/2 : ( 22/22 - 5/22 + 2/22) =
= 1/2 : 19/22 =
= 1/2 x 22/19 =
= 11/19
