7又2/9*1.1-6.81*9/97+68.1/(5又2/19)
=65/9*1.1-6.81*9/97+68.1*19/97
=71.5/9+6.81/97*(19-9)
=71.5/9+68.1/97
=(71.5*97+68.1*9)/(9*97)
=(6935.5+68.1)/873
=7003.6/873
=8.02245
7又2/9*1.1-6.81*9/97+68.1/(5又2/19)
=65/9*1.1-6.81*9/97+68.1*19/97
=71.5/9+6.81/97*(19-9)
=71.5/9+68.1/97
=(71.5*97+68.1*9)/(9*97)
=(6935.5+68.1)/873
=7003.6/873
=8.02245