1.
脱式计算我最棒!
(1)56+34×12
(2)(78-26)×15 (3)19×27-68 | (4)400-14×26
| (2)120×26-16×18 (3)(27+28)×25 | (4)3981-48×70
| (2)(1457-1432)×24 (3)(36+24)×40 | (4)3980-47×71
| (2)33.2-13.4-12.6 =33.2-(□○□) =□ (3)38×12 =38×□+38×□ =□ | (4)56×39 =56×□-56×□ =□(5)346-100+99-98+97-96+95-94+…+5-4+3-2+1 =346-□×□ =346-□ =□
| (2)(367-288)×27 | (3) l154-298+314 (4)810÷9×35 | (5)40×25-286 | (6)54×(116 - 29)
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