口算下面各题 (1)2.5+3.2= (2)9.8-4.8= (3)1.29-0.18= (4)2.26+0.9= (5)8-0.82= (6)0.75+0.25= (7)1.4+0.5= (8)10.8-8.5= (9)6.4+1.07= (10)0.55+5.5= (11)1.05-0.09= (12)0.6+6.45=
5×9= 45÷5= 45÷9= 4×9= 36÷4= 36÷9=
5×7= 35÷5= 35÷7= 2×8= 16÷2= 16÷8=
5×8= 40÷8= 40÷5= 7×3= 21÷7= 21÷3=
3×8= 24÷3= 24÷8= 6×8= 48÷6= 48÷8=
9×6= 54÷6= 54÷9= 7×4= 28÷7= 28÷4=