+= ﹣= 24×= 5﹣=
30÷= += +0.25= ÷=
523﹣23×7
4.97+6.38+5.03﹣4.38
60×()
×3.2+5.6×0.5+1.2×50%
()÷
40×18﹣60÷15
(12.5×8﹣60)÷0.4
3.14×2.77+0.223×31.4
①3.9×2.5×4
② ÷[ ×( - )]
③ × + ÷
① ÷8+ ×
②101×6.9