Question

8．口算

7×$\frac{7}{6}$=	$\frac{13}{70}$×0=	$\frac{5}{9}$-$\frac{1}{5}$=	$\frac{15}{7}$×$\frac{21}{20}$=
9×$\frac{9}{8}$=	16×$\frac{7}{8}$=	$\frac{2}{6}$+$\frac{1}{4}$=	$\frac{5}{9}$×$\frac{18}{35}$=
$\frac{1}{5}$×$\frac{3}{4}$=	7.8×$\frac{10}{39}$=	$\frac{7}{15}$×5=	$\frac{7}{9}$×1=
$\frac{1}{10}$×$\frac{5}{8}$=	1.5×$\frac{3}{5}$=	$\frac{5}{6}$×$\frac{9}{20}$=	$\frac{9}{29}$×58=
2.4×$\frac{5}{6}$=	$\frac{13}{20}$×$\frac{2}{39}$=	$\frac{2}{11}$×$\frac{22}{33}$=	$\frac{4}{5}$×$\frac{1}{4}$=

Answer 1

分析 根據(jù)分?jǐn)?shù)乘法的計(jì)算法則進(jìn)行口算即可．

解答 解：

7×$\frac{7}{6}$=$\frac{49}{6}$	$\frac{13}{70}$×0=0	$\frac{5}{9}$-$\frac{1}{5}$=$\frac{16}{45}$	$\frac{15}{7}$×$\frac{21}{20}$=$\frac{9}{4}$
9×$\frac{9}{8}$=$\frac{91}{8}$	16×$\frac{7}{8}$=14	$\frac{2}{6}$+$\frac{1}{4}$=$\frac{7}{12}$	$\frac{5}{9}$×$\frac{18}{35}$=$\frac{2}{7}$
$\frac{1}{5}$×$\frac{3}{4}$=$\frac{3}{20}$	7.8×$\frac{10}{39}$=2	$\frac{7}{15}$×5=$\frac{7}{3}$	$\frac{7}{9}$×1=$\frac{7}{9}$
$\frac{1}{10}$×$\frac{5}{8}$=$\frac{1}{16}$	1.5×$\frac{3}{5}$=0.9	$\frac{5}{6}$×$\frac{9}{20}$=$\frac{3}{8}$	$\frac{9}{29}$×58=18
2.4×$\frac{5}{6}$=2	$\frac{13}{20}$×$\frac{2}{39}$=$\frac{1}{30}$	$\frac{2}{11}$×$\frac{22}{33}$=$\frac{4}{33}$	$\frac{4}{5}$×$\frac{1}{4}$=$\frac{1}{5}$

點(diǎn)評(píng) 此題考查了分?jǐn)?shù)乘法的計(jì)算法則的運(yùn)用．