3 целых 5/9+(-2 целых 1/4)-(-4 целых 5/6)-5 целых 2/3
3 5/9+(-2 1/4)-(-4 5/6)-5 2/3=
=3 5/9 - 2 1/4+4 5/6-5 2/3=
=32/9-9/4+29/6-17/3=
=(32*4-9*9+29*6-17*12)/36=
=(128-81+174-204)/36=17/36