Question

3．直接写出得数．

$\frac{9}{14}$×$\frac{7}{27}$=	6÷$\frac{1}{3}$=	$\frac{8}{17}$÷$\frac{2}{17}$=	$\frac{1}{6}$+$\frac{3}{4}$=
$\frac{2}{5}$×$\frac{5}{12}$=	0÷$\frac{14}{33}$=	$\frac{1}{8}$×$\frac{1}{7}$=	9×$\frac{1}{9}$÷$\frac{1}{9}$×9=
$\frac{3}{5}$-$\frac{3}{5}$=	$\frac{1}{4}$×$\frac{1}{5}$÷$\frac{1}{4}$×$\frac{1}{5}$=

Answer 1

分析 根据分数加减乘除法的计算方法进行计算；
9×$\frac{1}{9}$÷$\frac{1}{9}$×9、$\frac{1}{4}$×$\frac{1}{5}$÷$\frac{1}{4}$×$\frac{1}{5}$根据乘法交换律和结合律进行简算．

解答 解：

$\frac{9}{14}$×$\frac{7}{27}$=$\frac{1}{6}$	6÷$\frac{1}{3}$=18	$\frac{8}{17}$÷$\frac{2}{17}$=4	$\frac{1}{6}$+$\frac{3}{4}$=$\frac{11}{12}$
$\frac{2}{5}$×$\frac{5}{12}$=$\frac{1}{6}$	0÷$\frac{14}{33}$=0	$\frac{1}{8}$×$\frac{1}{7}$=$\frac{1}{56}$	9×$\frac{1}{9}$÷$\frac{1}{9}$×9=81
$\frac{3}{5}$-$\frac{3}{5}$=0	$\frac{1}{4}$×$\frac{1}{5}$÷$\frac{1}{4}$×$\frac{1}{5}$=$\frac{1}{25}$

点评 口算时，注意运算符号和数据，然后再进一步计算．