分析:(1)運(yùn)用加法的性質(zhì)以及加法交換律與結(jié)合律簡(jiǎn)算;
(2)運(yùn)用乘法分配律簡(jiǎn)算;
(3)把0.32看作0.4×0.8,運(yùn)用乘法結(jié)合律簡(jiǎn)算;
(4)先算括號(hào)內(nèi)的乘法,再算括號(hào)內(nèi)的減法,最后算括號(hào)外的除法;
(5)把10.1看作10+0.1,運(yùn)用乘法分配律簡(jiǎn)算;
(6)先算小括號(hào)內(nèi)的,再算中括號(hào)內(nèi)的,最后算括號(hào)外的除法.
解答:解:(1)53.85-(4.13+3.85)
=53.85-4.13-3.85
=(53.85-3.85)-4.13
=50-4.13
=45.87;
(2)1.28×8.5+0.72×8.5
=(1.28+0.72)×8.5
=2×8.5
=17;
(3)25×0.32×1.25
=25×0.4×0.8×1.25
=(25×0.4)×(0.8×1.25)
=10×1
=10;
(4)40.8÷(41.5-7.5×5)
=40.8÷(41.5-37.5)
=40.8÷4
=10.2;
(5)28.6×10.1
=28.6×(10+0.1)
=28.6×10+0.1×28.6
=286+2.86
=288.86;
(6)[8.85-(1.5+3.75)]÷1.8
=[8.85-5.25]÷1.8
=3.6÷1.8
=2.
點(diǎn)評(píng):此題考查了小數(shù)的四則混合運(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)算定律簡(jiǎn)便計(jì)算.