(1)2.5×7.1×4,
=(2.5×4)×7.1,
=10×7.1,
=71;
(2)16.12×99+16.12,
=16.12×(99+1),
=16.12×100,
=1612;
(3)5.2×0.9+0.9×4.8,
=0.9×(5.2+4.8),
=0.9×10,
=9;
(4)[113-(34.15+38.25)]÷2,
=[113-72.4]÷2,
=40.6÷2,
=20.3;
(5)3.6÷(1.2+0.6)×0.5,
=3.6÷1.8×0.5,
=2×0.5,
=1;
(6)4.82÷0.25+1.25÷0.25,
=4.82×4+1.25×4,
=19.28+5,
=24.28.
分析:(1)運(yùn)用乘法的交換律及結(jié)合律進(jìn)行計(jì)算.
(2)、(3)運(yùn)用乘法的分配律進(jìn)行計(jì)算,使計(jì)算更加簡(jiǎn)便.
(4)、(5)、(6)根據(jù)四則混合運(yùn)算的運(yùn)算順序計(jì)算即可.
點(diǎn)評(píng):考查了運(yùn)算定律與簡(jiǎn)便運(yùn)算,四則混合運(yùn)算.注意運(yùn)算順序和運(yùn)算法則,靈活運(yùn)用所學(xué)的運(yùn)算律簡(jiǎn)便計(jì)算.