1000-90-10-80-20-70-30-60-40-50-50
80÷20= 400÷50= 240÷80= 450÷(9×5)=
630÷90= 52÷4= 24×30= 270÷6÷5=
160×50= 265+70= 300÷50= 0÷44+6=
306÷3= 500-397= 101×40= 32-12×0=
①40×25=
②280÷7
③142+68=
④88+0÷22=
⑤39×203≈
⑥4500÷900=
⑦5×307=
⑧1200÷60=
⑨7200÷(60+12)=
⑩558÷78≈
①450÷9×31
②380-725÷5
③(250-45×4)×8
④600÷[(11+25)÷9]
228+(72+189 )
109+(291-176)
483-236-64
1022-478-422
987-(287+135)
478-256-144
487-287-139-61
500-257-43
(136+152)÷32 664÷83×632
89 370 10.1×37