①
②()÷
③
④-(÷-)
⑤19×(+)×37
⑥÷[(-)×6]
=
12.5×8=
3.14×102=
144÷12=
33÷11%=
×40=
÷=
×=
×2.1=
0÷=
20×45%=
25%÷=
1÷×=
×÷×=