考點:整數(shù)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)運用減法的性質簡算.
(2)(4)(18)從左往右依次計算.
(3)運用減法的性質簡以及加法交換律與結合律簡算.
(5)(6)(17)運用加法交換律與結合律簡算.
(7)(8)(9)(10)(11)(16)運用除法的性質簡算.
(12)先算括號內的,再算括號外的.
(13)把24看作3×8,運用乘法結合律簡算.
(14)調換運算順序簡算.
(15)把72看作8×9,運用乘法結合律簡算.
(19)把350看作70×5,運用除法的性質簡算.
(20)運用除法的性質簡算.
(21)(22)(23)(24)運用乘法分配律簡算.
解答:
解:(1)1800-182-218
=1800-(182+218)
=1800-400
=1400
(2)1543-287+13
=1256+13
=1269
(3)543-(24+43)
=543-24-43
=(543-43)-24
=500-24
=476
(4)1010-569+431
=441+431
=872
(5)2350-788-1350
=(2350-1350)-788
=1000-788
=212
(6)387+256+(144+113)
=(387+113)+(256+144)
=500+400
=900
(7)7800÷25÷4
=7800÷(25×4)
=7800÷100
=78
(8)1200÷(12×4)
=1200÷12÷4
=100÷4
=25
(9)7800÷(39×50)
=7800÷39÷50
=200÷50
=4
(10)48000÷(125×48)
=48000÷125÷48
=48000÷48÷125
=1000÷125
=8
(11)5600÷14÷4
=5600÷(14×4)
=5600÷56
=100
(12)4800÷(64÷8)
=4800÷8
=600
(13)76+24×125
=76+3×8×125
=76+3×(8×125)
=76+3×1000
=76+3000
=3076
(14)275×8÷275
=275÷275×8
=1×8
=8
(15)72×125
=9×8×125
=9×(8×125)
=9×1000
=9000
(16)3500÷4÷25
=3500÷(4×25)
=3500÷100
=35
(17)973-215-73-185
=(973-73)-(215+185)
=900-400
=500
(18)493-256+144
=237+144
=381
(19)9100÷350
=9100÷(70×5)
=9100÷70÷5
=130÷5
=26
(20)34800÷2300
=34800÷(23×100)
=34800÷23÷100
=34800÷100÷23
=348÷23
=15
(21)(25+72)×40
=25×40+72×40
=1000+2880
=3880
(22)44×56+56×56
=(44+56)×56
=100×56
=5600
(23)99×99+99
=99×(99+1)
=99×100
=9900
(24)49×49+49+49×49
=49×(49+1+49)
=49×99
=49×(100-1)
=49×100-49
=4900-49
=4851
(25)125×(5×78+3×78)
=125×78×(5+3)
=125×78×8
=(125×8)×78
=1000×78
=78000
(26)456+79-56-79
=(456-56)+(79-79)
=400+0
=400
(27)108+(66+92+224)
=(108+92)+(66+224)
=200+290
=490
點評:此題主要考查整數(shù)的四則混合運算的運算順序和應用運算定律進行簡便計算.