Question

11．直接寫得數(shù)．

$\frac{1}{4}$×$\frac{2}{5}$=	$\frac{7}{12}$×$\frac{3}{14}$=	0.9×$\frac{3}{4}$=	9×$\frac{7}{18}$=	$\frac{2}{3}$×$\frac{9}{10}$=
$\frac{5}{8}$×$\frac{2}{5}$=	$\frac{4}{21}$×$\frac{7}{8}$=	39×$\frac{1}{13}$=	$\frac{8}{15}$×$\frac{9}{10}$=	80×$\frac{3}{4}$×$\frac{1}{3}$=

Answer 1

分析 根據(jù)分?jǐn)?shù)乘法的計算方法進(jìn)行計算，注意計算的結(jié)果要化成最簡分?jǐn)?shù)．

解答 解：

$\frac{1}{4}$×$\frac{2}{5}$=$\frac{1}{10}$	$\frac{7}{12}$×$\frac{3}{14}$=$\frac{1}{8}$	0.9×$\frac{3}{4}$=$\frac{27}{40}$	9×$\frac{7}{18}$=$\frac{7}{2}$	$\frac{2}{3}$×$\frac{9}{10}$=$\frac{3}{5}$
$\frac{5}{8}$×$\frac{2}{5}$=$\frac{1}{4}$	$\frac{4}{21}$×$\frac{7}{8}$=$\frac{1}{6}$	39×$\frac{1}{13}$=3	$\frac{8}{15}$×$\frac{9}{10}$=$\frac{12}{25}$	80×$\frac{3}{4}$×$\frac{1}{3}$=20

點(diǎn)評 本題考查了學(xué)生對分?jǐn)?shù)乘法計算方法的掌握，在計算時要細(xì)心．