⑴0.2×0.4=
8.2+1.8=
100-35.22=
⑵2.5×0.4=
2.4×5=
0.22×4=
⑶0.9-0.52=
3.99×1=
0.1×3.52=
⑷8.7×(2.86+7.14)=
2.5×6.45×4=