解:①34.8÷1.25÷8,
=34.8÷(1.25×8),
=34.8÷10,
=3.48;
②1.25×3.2×0.25,
=(1.25×8)×(0.4×0.25),
=10×0.1,
=1;
③36×25%+0.25×43+
,
=36×0.25+0.25+43+0.25,
=(36+43+1)×0.25,
=80×0.25,
=20;
④(2.7+12.5)÷0.5-5.6,
=15.2÷0.5-5.6,
=30.4-5.6,
=24.8.
分析:①34.8÷1.25÷8,運(yùn)用除法的運(yùn)算性質(zhì)進(jìn)行簡(jiǎn)算;
②1.25×3.2×0.25,把3.2分解為:8×0.4,再運(yùn)用乘法結(jié)合律進(jìn)行簡(jiǎn)算;
③36×25%+0.25×43+
,把25%、
,化成小數(shù)0.25,再運(yùn)用乘法分配律進(jìn)行簡(jiǎn)算;
④(2.7+12.5)÷0.5-5.6,根據(jù)小數(shù)四則混合運(yùn)算的順序,按照小數(shù)四則運(yùn)算的計(jì)算法則進(jìn)行計(jì)算.
點(diǎn)評(píng):此題主要考查小數(shù)四則混合運(yùn)算,要求學(xué)生牢固掌握運(yùn)算順序和計(jì)算法則,并且能夠靈活選擇簡(jiǎn)便方法進(jìn)行簡(jiǎn)算.