①535-384+279
②74+436-298
③422+233-195
④634-267-346
42-(18+9)
53-8×3
(88-56)÷8
① []
②4.6+7.68﹣1+2.32
③1.25×2.5×0.4×8
④9.5×20%+
①250-250÷25×2
②18÷ ×
③5.2÷0.4÷2.5
④(34- )÷17
⑤4.3×1.75-1.75+ ×6.7
⑥ ×[(72.8-69.6)÷ ]