Question

2道计算题,我要的是简便的.计算：211×（-455）+365×455-211×545+545×365=_____37.

Answer 1

37.9×0.0038+1.21×0.379+6.21×0.159=0.379*0.38+1.21*0.379++6.21×0.159=1.59*0.379 + 6.21×0.159=1.59*0.379 + 0.621×1.59=1.59*1=1.59