分析:(1)2.8×0.5+0.5×27.2根據(jù)乘法分配律進(jìn)行簡(jiǎn)算;
(2)3.56+6.1+6.44根據(jù)加法交換律和結(jié)合律進(jìn)行簡(jiǎn)算;
(3)17.67-2.77-2.23,根據(jù)減法的運(yùn)算性質(zhì),從一個(gè)數(shù)里連續(xù)減求兩個(gè)數(shù),可以轉(zhuǎn)化為從這個(gè)數(shù)里減去兩個(gè)減數(shù)的和,簡(jiǎn)算比較簡(jiǎn)便;
(4)11÷2.5÷0.4.根據(jù)除法的運(yùn)算性質(zhì),一個(gè)數(shù)連續(xù)除以兩個(gè)數(shù),可以轉(zhuǎn)化為用這個(gè)數(shù)除以兩個(gè)除數(shù)的積,這樣簡(jiǎn)算比較簡(jiǎn)便;
解答:解:(1)2.8×0.5+0.5×27.2
=(2.8+27.2)×0.5
=30×0.5
=15;
(2)3.56+6.1+6.44
=3.56+6.44+6.1
=10+6.1
=16.1;
(3)17.67-2.77-2.23
=17.67-(2.77+2.23)
=17.76-5
=12.76;
(4)11÷2.5÷0.4
=11÷(2.5×0.4)
=11÷1
=11.
點(diǎn)評(píng):此題這樣考查利用整數(shù)加法、乘法的運(yùn)算定律和減法、除法的運(yùn)算性質(zhì)對(duì)小數(shù)的四則運(yùn)算進(jìn)行簡(jiǎn)便計(jì)算.