估算342×7≈ 29×9≈ 3×502≈
653.54+17.16=★70﹣23.23=
直接写出得数:5.4+8.5= 150×6= 6.78+0.23= 10﹣6.5+3.5=7.5×100= 60×50= 287﹣199= 0.3×125×8=1﹣0.09= 927÷9= 60÷100= 6.3×99+6.3=0.61×99≈ 6.9×8.1≈ 71.9÷8.9≈ 3.5+0.78+6.5=
列竖式计算.(带*的题要验算)42.3+15.9=10﹣3.8=*15×68=32×26=
计算下面各题,并且验算:41.2﹣15.6 21.56+6.74.
(1)30﹣7.6= (2)7.8+5.2= (3)23×13=(4)836÷4= (5)38×24= (6)☆422÷7=