先用刻度尺度量出如图图形的相关线段的长度,再计算面积.
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=
口算. 10﹣4.2= 7.1﹣3.9= 4.3﹣4= 3.8+1.4= 5.7+1.8= 2.7﹣1.7= 0.5+8.5= 3.6﹣0.9=
森林医院.(找出题目中的错误,将正确的式子写在旁边空白处)
连线.