下面各题,你能用简便方法计算吗?1.0.76x9.9+0.076 2.11.72-(4.3x0.4+5.6) 3.12.5x(8+0.8-0.047)
问题描述:
下面各题,你能用简便方法计算吗?1.0.76x9.9+0.076 2.11.72-(4.3x0.4+5.6) 3.12.5x(8+0.8-0.047)
答
1.0.76x9.9+0.076 =0.076*99+0.076=(99+1)*0.076=100*0.076=7.62.11.72-(4.3x0.4+5.6)=10+1.72-1.72+5.6=15.63.12.5x(8+0.8-0.047)=12.5*8+12.5*0.8-12.5*0.04-12.5*0.007=100+10-0.5-0.0875=109.4125