一根圆柱形钢材,截下1米,量得它的横截面的半径是10厘米,截下的体积占这根钢材的,这根钢材原来的体积是多少立方分米?
从仓库里运走水泥85.6吨,还剩52.3吨.仓库里原有水泥多少吨?
计算:0.1+0.3+0.5+0.7+0.9+0.1 1+0.13+0.15+0.17+0.19.
用竖式计算下面各题,带※的要验算. ※4.32+3.08 ※13.7﹣9.65 1.5+8.36 10.5+12.4 6.75﹣3.15 8+11.07 1.5﹣0.06 1.53﹣0.7.
把下面的算式补充完整. 18.7﹣16.4+ =18.7+ ﹣l6.4 =20﹣16.4 = 35.67+ +21.35 =35.67+( +21.35) =35.67+50 = 54.37﹣ ﹣9.23 =54.37﹣( +9.23) =54.37﹣10 = 33.25+6.23﹣ =33.25﹣ +6.23 =30+6.23 = .
笔算下面各题. 2.8﹣1.9= 2.6+1.8= 3.2﹣1.5=