Найдите значение выражения: 6-2,2: (6 11/30-4 7/20) !

= 6 - 2,2:(191/30-78/40)=
=6-2,2:(7640/1200-2340/1200)=
=6-2,2:(53/12)=
=6-2,2•(12/53)=
=6-(22/10)•(12/53)=
=6-132/53=
=(318/53)-(132/53)=186/53=3 целых 27/53