18.75-(5又9分之2加上8又4分之1+2分1)
=18.75-(47/9+33/4+1/2)
=75/4-(47*4+33*9+18)/36
=675/36-(188+297+18)/36
=675/36-403/36
=(675-503)/36
=172/36
=43/9
18.75-(5又9分之2加上8又4分之1+2分1)
=18.75-(47/9+33/4+1/2)
=75/4-(47*4+33*9+18)/36
=675/36-(188+297+18)/36
=675/36-403/36
=(675-503)/36
=172/36
=43/9