-2/3+(-1/6)-(-1/4)-1/2=?(-7.8)×1.25×(-8)=?

问题描述:

-2/3+(-1/6)-(-1/4)-1/2=?(-7.8)×1.25×(-8)=?

=-8/12-(2/12)+(3/12)-(6/12)=(-8-2+3-6)/12=-13/12;
=7.8*(1.25*8)=7.8*10=78