Question

9．計(jì)算：
$\frac{4}{5}$÷2=$\frac{2}{5}$；$\frac{6}{7}$÷3=$\frac{2}{7}$；$\frac{4}{5}$÷5=$\frac{4}{5}$×$\frac{1}{5}$=$\frac{4}{25}$；$\frac{8}{13}$÷6=$\frac{8}{13}$×$\frac{1}{6}$=$\frac{4}{39}$；
$\frac{5}{7}$÷6=$\frac{5}{7}$×$\frac{1}{6}$=$\frac{5}{42}$；$\frac{7}{13}$÷7=$\frac{7}{13}$×$\frac{1}{7}$=$\frac{1}{13}$；$\frac{7}{12}$÷3=$\frac{7}{36}$；$\frac{5}{18}$÷10=$\frac{1}{36}$；$\frac{6}{7}$÷24=$\frac{1}{28}$；$\frac{7}{8}$÷28=$\frac{1}{32}$；$\frac{9}{20}$÷18=$\frac{1}{40}$．

Answer 1

分析 分?jǐn)?shù)除以整數(shù)：分?jǐn)?shù)除以整數(shù)（0除外），等于分?jǐn)?shù)乘以這個(gè)整數(shù)的倒數(shù)，據(jù)此解答即可．

解答 解：根據(jù)分?jǐn)?shù)除法的運(yùn)算方法，可得
$\frac{4}{5}$÷2=$\frac{2}{5}$；$\frac{6}{7}$÷3=$\frac{2}{7}$；$\frac{4}{5}$÷5=$\frac{4}{5}$×$\frac{1}{5}$=$\frac{4}{25}$；$\frac{8}{13}$÷6=$\frac{8}{13}$×$\frac{1}{6}$=$\frac{4}{39}$；
$\frac{5}{7}$÷6=$\frac{5}{7}$×$\frac{1}{6}$=$\frac{5}{42}$；$\frac{7}{13}$÷7=$\frac{7}{13}$×$\frac{1}{7}$=$\frac{1}{13}$；$\frac{7}{12}$÷3=$\frac{7}{36}$；$\frac{5}{18}$÷10=$\frac{1}{36}$；$\frac{6}{7}$÷24=$\frac{1}{28}$；$\frac{7}{8}$÷28=$\frac{1}{32}$；$\frac{9}{20}$÷18=$\frac{1}{40}$．
故答案為：$\frac{2}{5}、\frac{2}{7}、\frac{1}{5}、\frac{4}{25}、\frac{1}{6}、\frac{4}{39}$、6、$\frac{5}{42}、7、\frac{1}{7}、\frac{1}{13}、\frac{7}{36}、\frac{1}{36}、$$\frac{1}{28}、\frac{1}{32}、\frac{1}{40}$．

點(diǎn)評(píng) 此題主要考查了分?jǐn)?shù)除法的運(yùn)算方法，要熟練掌握．