①
②
③
④
⑤
⑥
①( - ÷4)×
② ×99+
③2.7÷(1-20%-50%)
④(6.7×60%+3.3×60%)÷
⑤10×( - ÷37.5%)
15×60= 640÷40= ÷ = 398÷202≈ 6.9÷0.1=
1.05-0.65= 0.8×125%= 5- = ÷6= 910-430=