分析:(1)根據(jù)商不變規(guī)律,被除數(shù)和除數(shù)同時(shí)除以9,然后再計(jì)算;
(2)先把36分解成4×9,再運(yùn)用乘法結(jié)合律簡算;
(3)(9)根據(jù)除法的性質(zhì)簡算;
(4)把99分解成(100-1),再運(yùn)用乘法分配律簡算;
(5)(6)(7)(8)運(yùn)用乘法分配律簡算.
解答:解:(1)270÷45
=(270÷9)÷(45÷9)
=30÷5
=6;
(2)25×36
=25×(4×9)
=25×4×9
=100×9
=900;
(3)460÷5÷2
=460÷(5×2)
=460÷10
=46;
(4)99×23
=(100-1)×23
=100×23-1×23
=2300-23
=2277;
(5)85×82+82×15
=(85+15)×82
=100×82
=8200;
(6)58+32+53+47
=(58+32)+(53+47)
=90+100
=190;
(7)72×48-72×38
=72×(48-38)
=72×10
=720;
(8)125×(8+80)
=125×8+125×80
=1000+10000
=11000
(9)800÷(80×2)
=800÷80÷2
=10÷2
=5.
點(diǎn)評:完成本題要注意分析式中數(shù)據(jù),運(yùn)用合適的簡便方法計(jì)算.