Question

4．脫式計(jì)算（能簡(jiǎn)算的要簡(jiǎn)算）
（$\frac{2}{29}$+$\frac{3}{23}$）×29×23
$\frac{3}{8}$×33+66×37.5%+0.375
$\frac{5}{8}$÷[1-（0.75+$\frac{1}{12}$）]．

Answer 1

分析 ①用乘法分配律計(jì)算，（a+b）×c=ac+bc．
②用乘法分配律計(jì)算，ac+bc=（a+b）×c．
③先算加法再算減法，最后算除法．

解答 解：①（$\frac{2}{29}$+$\frac{3}{23}$）×29×23
=$\frac{2}{29}$×29×23+$\frac{3}{23}$×29×23
=46+87
=133

②$\frac{3}{8}$×33+66×37.5%+0.375
=（33+66+1）×0.375
=100×0.375
=37.5

③$\frac{5}{8}$÷[1-（0.75+$\frac{1}{12}$）]
=$\frac{5}{8}$÷[1-$\frac{5}{6}$]
=$\frac{5}{8}×\frac{6}{1}$
=$\frac{15}{4}$

點(diǎn)評(píng) 本題考查了四則混合運(yùn)算的計(jì)算能力，完成時(shí)要細(xì)心，注意小數(shù)、分?jǐn)?shù)之間的互化及通分約分．