3.5×0.4= 7.2÷0.8= 4÷8= 2.9a+4.5a=
3.6+5.7= 4.5-2.8= 42×5= 1.25×0.7×8=
1.6÷0.16= 12-0.9= 0.32= 0.25×4÷0.25×4=