考點:整數四則混合運算,運算定律與簡便運算
專題:運算順序及法則,運算定律及簡算
分析:(1)(8)(10)利用加法交換律與結合律簡算;
(2)(9)湊整計算,多加的要減去,多減的要加上;
(3)(6)利用減法的性質簡算;
(4)利用乘法交換律簡算;
(5)(7)利用除法的性質簡算.
解答:
解:(1)263+65+35+337
=263+337+(65+35)
=500+100
=600;
(2)409+296
=409+300-4
=709-4
=705;
(3)465-(22+165)
=465-165-22
=300-22
=278;
(4)40×(17×5)
=40×5×17
=200×17
=3400;
(5)420÷35
=420÷7÷5
=60÷5
=12;
(6)613-78-22
=613-(78+22)
=613-100
=513;
(7)540÷15÷4
=540÷(15×4)
=540÷60
=9;
(8)178+(147+122)
=178+122+147
=300+147
=447;
(9)367-298
=367-300+2
=67+2
=69;
(10)946+117-146
=946-146+117
=800+117
=917.
點評:整數混合運算的關鍵是抓住運算順序,正確按運算順序計算,適當利用運算定律簡算.