①4.05÷0.81+2.4
②4.85×8×1.25
③31.9×8-0.8×19
④
⑤
⑥
783+199=
494-298=
-=
+=
0.5+=
×=
÷=
1÷25%=
99×9+99=
2-15%=
5÷(1+)= 4×0.5= 0.75×= 1﹣1×=
+×= 24÷= ×0.25= +=
10﹣= 1﹣×= ×6÷×6= 1÷×=
①
②3.7×+13÷
③
④7÷(+0.875)
⑤22×+25×75%-6×0.75-
⑥37×
②
⑦×(×)
⑧(20+)÷
⑨÷(-)
①÷×12
②1-÷0.9
③0.4×+×
④57×
⑤14×(-)×13
⑥÷(3--)