Question

3．直接寫出計(jì)算結(jié)果．

$\frac{3}{8}$×$\frac{16}{17}$	（$\frac{1}{2}$+$\frac{1}{5}$）×1	10÷$\frac{2}{5}$
2-$\frac{3}{5}$÷$\frac{3}{5}$	1÷$\frac{2}{3}$×$\frac{2}{3}$	$\frac{5}{8}$×0.25-0.25×$\frac{3}{8}$

Answer 1

分析 根據(jù)分?jǐn)?shù)、小數(shù)加減乘除法的計(jì)算方法進(jìn)行計(jì)算．
$\frac{5}{8}$×0.25-0.25×$\frac{3}{8}$，根據(jù)乘法分配律進(jìn)行簡(jiǎn)算．

解答 解：

$\frac{3}{8}$×$\frac{16}{17}$=$\frac{6}{17}$	（$\frac{1}{2}$+$\frac{1}{5}$）×1=$\frac{7}{10}$	10÷$\frac{2}{5}$=25
2-$\frac{3}{5}$÷$\frac{3}{5}$=1	1÷$\frac{2}{3}$×$\frac{2}{3}$=1	$\frac{5}{8}$×0.25-0.25×$\frac{3}{8}$=$\frac{1}{16}$

點(diǎn)評(píng) 口算時(shí)，注意運(yùn)算符號(hào)和數(shù)據(jù)，然后再進(jìn)一步計(jì)算．