分析:(1)運(yùn)用加法交換律和結(jié)合律簡(jiǎn)算;
(2)(4)(5)運(yùn)用乘法分配律簡(jiǎn)算;
(3)運(yùn)用乘法交換律與結(jié)合律簡(jiǎn)算;
(6)把98看作100-2,運(yùn)用乘法分配律簡(jiǎn)算;
(7)先算除法和乘法,再算減法;
(8)先算括號(hào)內(nèi)的,再算括號(hào)外的除法最后算乘法;
(9)先算擴(kuò)阿紅誒的處罰,再算括號(hào)內(nèi)的加法,最后算括號(hào)外的減法;
(10)先算括號(hào)內(nèi)的,再算括號(hào)外的;也可先去括號(hào),從左往右依次計(jì)算;
(11)按運(yùn)算順序,從左往右依次計(jì)算;
(12)先算括號(hào)內(nèi)的,從左往右依次計(jì)算,最后算括號(hào)外的減法.
解答:解:(1)1.29+3.7+0.71+6.3,
=(1.29+0.71)+(6.3+3.7),
=2+10,
=12;
(2)528×78-428×78,
=(528-428)×78,
=100×78,
=7800;
(3)125×(92×8),
=(125×8)×92,
=1000×92,
=92000;
(4)57×101-57,
=57×(101-1),
=57×100,
=5700;
(5)(40+4)×25,
=40×25+4×25,
=1000+100,
=1100;
(6)35×98,
=35×(100-2),
=3500-70,
=3430;
(7)19×96-962÷74,
=19×(100-4)-13,
=1900-76-13,
=1900-(76+13),
=1900-89,
=1811;
(8)(520+480)÷50×4,
=1000÷50×4,
=20×4,
=80;
(9)400-(1300÷65+35),
=400-(20+35),
=400-55,
=345;
(10)86.7-(14.3-3.8),
=86.7-10.5,
=76.2;
(11)72.8-8.6+5.84,
=64.2+5.84,
=70.04;
(12)40-(3.5-2.75+0.86),
=40-1.61,
=38.39.
點(diǎn)評(píng):完成本題要注意運(yùn)算順序,同時(shí)注意分析式中數(shù)據(jù),運(yùn)用合適的簡(jiǎn)便方法計(jì)算.