-24*(1又3/8+2又1/3-3.75)=-24*(11/8+7/3-15/4)=-24*11/8-24*7/3+24*15/4=-33-56+90=1
-24*(1又3/8+2又1/3-3.75) =-24×(1+2-3)-24×3/8-24×1/3+24×0.75=-9-8+18=1