Question

(5-0.5)×31.4简算

计算下面各题，能简算的要简算．
0.25×4×0.8×0.125
5.5×7.3+2.7×5.5
31.7-0.5×0.7-1.65
8.4×0.6+0.74．

Answer 1

①0.25×4×0.8×0.125
=（0.25×4）×（0.8×0.125）
=1×0.1
=0.1；

②5.5×7.3+2.7×5.5
=5.5×（7.3+2.7）
=5.5×10
=55；

③31.7-0.5×0.7-1.65
=31.5-（0.35+1.65）
=31.5-2
=29.5；

④8.4×0.6+0.74
=5.04+0.74
=5.78．