Question

13．直接寫出得數(shù)．

$\frac{3}{5}$×2=	4×$\frac{1}{2}$=	$\frac{3}{6}$×$\frac{2}{5}$=	$\frac{1}{4}$×$\frac{1}{2}$=
$\frac{6}{7}$×2=	$\frac{7}{9}$×$\frac{3}{7}$=	$\frac{5}{8}$×$\frac{2}{3}$=	$\frac{3}{11}$×3=

Answer 1

分析 根據(jù)分?jǐn)?shù)乘法的計算方法的計算，能約分的要先約分．

解答 解：

$\frac{3}{5}$×2=$\frac{6}{5}$	4×$\frac{1}{2}$=2	$\frac{3}{6}$×$\frac{2}{5}$=$\frac{1}{5}$	$\frac{1}{4}$×$\frac{1}{2}$=$\frac{1}{8}$
$\frac{6}{7}$×2=$\frac{12}{7}$	$\frac{7}{9}$×$\frac{3}{7}$=$\frac{1}{3}$	$\frac{5}{8}$×$\frac{2}{3}$=$\frac{5}{12}$	$\frac{3}{11}$×3=$\frac{9}{11}$

點評 本題考查了分?jǐn)?shù)乘法計算的口算能力，計算結(jié)果應(yīng)該是最簡分?jǐn)?shù)．