(3.91+3又7分之3+6.09+6又7分之4)*(2又8分之1-1.125)+(1/3分之2-1.5)*6.04
=(3.91+6.09+3又7分之3+6又7分之4)*(2.125-1.125)+(3/2-1.5)*6.04
=(10+10)*1+0*6.04
=20