3.1+0.4= += 640÷16= ×3×4=
10÷= ×= 2.4×= 25×40%=
8.47﹣3.98=
0.125+=
4.5×=
×0.25+×0.25=
1.69+0.1=
÷=
0.52=
﹣=
2.6×0.25×4=
﹣×0=
9.9×9+9.9=
×÷=
0.52+0.48=
1.2﹣0.6=
0.5÷0.01=
0.125+ =
2.5×0.2=
46×10%=
+ =
4÷ =
= 2.4×5= = 0.32=
= = =
每分钟注入水量/升
20
30
________
所需时间/分钟
10
5
×30= 0.5+ = =
= =