0.5m=cm
3.5+0.8=
3﹣1.6=
0.23÷0.1=
3.14×4=
× =
﹣ =
1﹣ + =
+ × =
①100﹣600÷25×4
②20﹣ ﹣
③13× +5×
④[ ﹣( + )]÷
①30x=15
②5x﹣3=5.5
③ :0.8=x:48
这个沙坑大约要填沙多少吨?