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)運用加法的交換律、結(jié)合律及減法的性質(zhì)進行簡算;
(2)運用減法的性質(zhì)進行簡算;
(3)先去括號,再從左向右進行計算;
(4)把299化成300-1進行計算即可;
(5)運用除法的性質(zhì)進行簡算;
(6)把99看出100-1,再運用乘法的分配律進行計算;
(7)先算乘法,再從左向右進行計算;
(8)先算小括號里的除法,再算小括號里的減法,最后算括號外的除法;
(9)先分別計算出乘法和除法,再算減法;
(10)運用乘法的分配律進行計算;
(11)運用除法的性質(zhì)進行簡算;
(12)運用乘法的分配律進行計算.
解答:
解:(1)468-128+132-372
=(468+132)-(128+372)
=600-500
=100;
(2)2196-884-116-196
=2196-196-(884+116)
=2000-1000
=1000;
(3)1998-(998-379)
=1998-998+379
=1000+379
=1379;
(4)345+299
=345+300-1
=645-1
=644;
(5)800÷24
=800÷8÷3
=100÷3
=
;
(6)67×99
=67×(100-1)
=67×100-67×1
=6700-67
=6633;
(7)3562-14×209+288
=3562-2926+288
=636+288
=924;
(8)1073÷(59-720÷24)
=1073÷(59-30)
=1073÷29
=37;
(9)36×28-2400÷15
=1008-160
=848;
(10)36×109-36×9
=36×(109-9)
=36×100
=3600;
(11)1308÷25÷4
=1308÷(25×4)
=1308÷100
=13.08;
(12)121×78+121×23-121
=121×(78+23-1)
=121×100
=12100.
點評:此題主要考查整數(shù)四則混合運算,要求學生掌握運算順序和計算法則,并且能夠靈活選擇簡便方法進行簡算.