Решите уравнение
7 7/30-(5 11/30 - y)= 3 19/30

7 7/30-(5 11/30-у)=3 19/30,

7 7/30- 5 11/30+у=3 19/30,

2 7/30-11/30+у=3 19/30,

67/30-11/30+у=3 19/30,

56/30+у=109/30,

у= 109/30-56/30,

у=53/30,

у=1 23/30  

проверка

7 7/30-(5 11/30-1 23/30)= 3 19/30,  7 7/30-(4 11/30-23/30)= 3 19/30,

7 7/30-(131/30-23/30)=3 19/30, 217/30-108/30= 3 19/30,  109/30= 3 19/30, 3 19/30=3 19/30