6/5×(-1/3-1/2)
=6/5×[(-2/6)+(-3/6)]
=6/5×(-5/6)
=-(6/5×5/6)
=-1
(-7/8+1又3/4-7/12)×(-1又1/7)
=(-7/8+7/4-7/12)×(-8/7)
=(-7/8)×(-8/7)+7/4×(-8/7)-7/12×(-8/7)
=1-2+2/3
=-1/3
(-8/25)×1.25×(-8)
=(-8/25)×5/4×(-8)
=8/25×5/4×8
=16/5
25×3/4-(-25)×1/2-25×1/4
=25×3/4+25×1/2-25×1/4
=25×(3/4+1/2-1/4)
=25×1
=25