31/8: ((3 13/24-4 5/12)*4/7+(2 7/12-3 1/18)*1 10/17) решить пример

3 13/24-4 5/12=3 13/24-4 10/24=3 13/24-3 34/24=-21/24=-7/8
2 7/12-3 1/18=2 21/36-3 2/36=2 21/36-2 38/36=-17/36
-7/8*4/7=-1/2
-17/36-1/2=-17/36-18/36=-35/36
-35/36*1 10/17=-35/36*27/17=-105/68
3 1/8:(-105/68)=-25/8*68/105=-85/21=-4 1/21