分析:①1.08×0.8÷0.27,先算乘法再算除法;
②102×0.45,運(yùn)用乘法分配律簡算;
③2.33×0.5×4,運(yùn)用乘法結(jié)合律簡算;
④9.07-22.78÷3.4先算除法,再算減法;
⑤44.28÷0.9÷4.1,按照從左到右的順序進(jìn)行計(jì)算;
⑥1.2×2.5+0.8×2.5,運(yùn)用乘法分配律簡算;
⑦[0.15+(2.4-1.8)]×20,先算小括號里面的,再算中括號里面,最后算括號外面的;
⑧0.78×[12-(1.45+3.8)].先算小括號里面的,再算中括號里面,最后算括號外面的.
解答:解:①1.08×0.8÷0.27
=0.864÷0.27
=3.2;
②102×0.45
=100×0.45+2×0.45
=45+0.9
=45.9;
③2.33×0.5×4
=2.33×(0.5×4)
=2.33×2
=4.66;
④9.07-22.78÷3.4
=9.07-6.7
=2.37;
⑤44.28÷0.9÷4.1
=49.2÷4.1
=12;
⑥1.2×2.5+0.8×2.5
=(1.2+0.8)×2.5
=2×2.5
=5;
⑦[0.15+(2.4-1.8)]×20
=[0.15+0.6]×20
=2.1×20
=42;
⑧0.78×[12-(1.45+3.8)]
=0.78×[12-5.25]
=0.78×6.75
=5.265.
點(diǎn)評:此題考查的目的是理解正確小數(shù)四則混合運(yùn)算的順序及它們的實(shí)際法則,并且能夠靈活運(yùn)用乘法的運(yùn)算定律進(jìn)行簡便計(jì)算.