17.2+2.8=
0.6×0.9=
8÷0.8=
0.25a+0.5a=
123÷100=
0.74×100=
2.7÷3=
3-1.48=
0.25a+0.05×2=
2.4-=
5-7÷14=
8.4--=
-1.125=
0.43=
0.7+=
=
3 和9 4和20
÷5= ÷4= 3÷= 0÷=
10÷= ÷= ÷= ÷=
20×70%= 40%+70%= 25%×40= 75%+=
0.2×2.7%= 15÷1%= 1.05﹣50%= 100×100%=