①2x﹣4×0.5=4
②:=x:
10﹣5.2=
7÷=
4×0.5=
0.52÷0.42=
48÷0.04=
48×25%=
1÷1%=
3.5+6.45=
657﹣298=
2.4×=
562÷79≈
21×498≈
3.5+2.5= 10﹣0.35= 0.56÷0.7= 20%×5%= 12:2.4=
25×0.8= 9﹣2= 3.75+1= 0÷18= :=
1.2×0.3= ﹣= 32÷53×0=
0.25÷= 1﹣0.09= +20%=