Question

19．直接寫出得數．

$\frac{1}{3}$×0=	$\frac{1}{4}$×$\frac{2}{5}$=	$\frac{5}{6}$×12=	$\frac{7}{12}$×$\frac{3}{14}$=	$\frac{4}{11}$×$\frac{11}{4}$=
9×$\frac{7}{18}$=	$\frac{2}{3}$×$\frac{9}{10}$=	$\frac{4}{25}$×100=	18×$\frac{1}{6}$=	$\frac{8}{15}$×$\frac{9}{10}$=

Answer 1

分析 分數乘法：分子相乘的積做分子，分母相乘的積做分母，能約分的先約分．

解答 解：

$\frac{1}{3}$×0=0	$\frac{1}{4}$×$\frac{2}{5}$=$\frac{1}{10}$	$\frac{5}{6}$×12=10	$\frac{7}{12}$×$\frac{3}{14}$=$\frac{1}{8}$	$\frac{4}{11}$×$\frac{11}{4}$=1
9×$\frac{7}{18}$=$\frac{7}{2}$	$\frac{2}{3}$×$\frac{9}{10}$=$\frac{3}{5}$	$\frac{4}{25}$×100=16	18×$\frac{1}{6}$=3	$\frac{8}{15}$×$\frac{9}{10}$=$\frac{12}{25}$

點評 此題考查了分數乘法的口算能力．