(-270)*1/4+0.25*21.5+(-8 1/2)*(-25%)

问题描述:

(-270)*1/4+0.25*21.5+(-8 1/2)*(-25%)
(-270)*1/4+0.25*21.5+(-8 1/2)*(-25%)

原式=(-270)×1/4+43/2×1/4+17/2×1/4
=1/4×(-270+43/2+17/2)
=1/4×(-240)
=-60