在( )里填上合适的数
$\frac{8}{14}=\frac{(\ \ \ \ \ )}{7}$ $\frac{8}{12}=\frac{16}{(\ \ \ \ \ )}=\frac{(\ \ \ \ \ )}{36}=\frac{2}{(\ \ \ \ \ )}$
$\frac{16}{40}=\frac{(\ \ \ \ \ )}{10}$ $\frac{1}{9}=\frac{3}{(\ \ \ \ \ )}=\frac{(\ \ \ \ \ )}{18}=\frac{5}{(\ \ \ \ \ )}$
$\frac{1}{9}=\frac{(\ \ \ \ \ )}{81}$ $\frac{9}{15}=\frac{9\div(\ \ \ \ \ )}{15\div(\ \ \ \ \ )}=\frac{3}{(\ \ \ \ \ )}$
$\frac{3}{7}=\frac{12}{(\ \ \ \ \ )}$ $\frac{2}{5}=\frac{2\times(\ \ \ \ \ )}{5\times(\ \ \ \ \ )}=\frac{(\ \ \ \ \ )}{30}$
$\frac{9}{21}=\frac{3}{(\ \ \ \ \ )}$ $\frac{14}{42}=\frac{(\ \ \ \ \ )}{21}=\frac{2}{(\ \ \ \ \ )}=\frac{(\ \ \ \ \ )}{3}$
$\frac{16}{24}=\frac{2}{(\ \ \ \ \ )}$ $\frac{48}{60}=\frac{8}{(\ \ \ \ \ )}=\frac{(\ \ \ \ \ )}{15}=\frac{16}{(\ \ \ \ \ )}$
$\frac{6}{14}=\frac{3}{(\ \ \ \ \ )}=\frac{(\ \ \ \ \ )}{28}$ $\frac{2}{3}=\frac{(\ \ \ \ \ )}{6}=\frac{6}{(\ \ \ \ \ )}$
$\frac{15}{20}=\frac{(\ \ \ \ \ )}{4}=\frac{12}{(\ \ \ \ \ )}$ $\frac{16}{48}=\frac{(\ \ \ \ \ )}{12}=\frac{(\ \ \ \ \ )}{3}$
$\frac{42}{63}=\frac{(\ \ \ \ \ )}{3}=\frac{6}{(\ \ \ \ \ )}$ $\frac{8}{(\ \ \ \ \ )}=\frac{2}{8}=\frac{(\ \ \ \ \ )}{16}$
$\frac{3}{42}=\frac{1}{(\ \ \ \ \ )}=\frac{(\ \ \ \ \ )}{56}$ $\frac{5}{25}=\frac{1}{(\ \ \ \ \ )}=\frac{(\ \ \ \ \ )}{75}$
$\frac{5}{(\ \ \ \ \ )}=\frac{15}{75}=\frac{(\ \ \ \ \ )}{20}$ $\frac{8}{10}=\frac{(\ \ \ \ \ )}{5}=\frac{40}{(\ \ \ \ \ )}$
$\frac{20}{28}=\frac{(\ \ \ \ \ )}{7}=\frac{(\ \ \ \ \ )}{56}$ $\frac{8}{100}=\frac{(\ \ \ \ \ )}{50}=\frac{16}{(\ \ \ \ \ )}$
$\frac{9}{12}=\frac{3}{(\ \ \ \ \ )}=\frac{(\ \ \ \ \ )}{20}$ $\frac{(\ \ \ \ \ )}{9}=\frac{18}{81}=\frac{12}{(\ \ \ \ \ )}$
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