a)
\(\dfrac{5}{6}< \dfrac{7}{6}\)
\(2=\dfrac{6}{3}\)
\(\dfrac{3}{7}>\dfrac{4}{14}\) (vì \(\dfrac{4}{14}=\dfrac{2}{7}\))
\(\dfrac{12}{20}< \dfrac{4}{5}\) (vì \(\dfrac{12}{20}=\dfrac{3}{5}\))
b)
\(\dfrac{1}{13}=\dfrac{3}{39};\dfrac{25}{13}=\dfrac{75}{39}\)
\(\dfrac{75}{39}>\dfrac{4}{39}>\dfrac{3}{39}\rightarrow\dfrac{75}{39},\dfrac{4}{39},\dfrac{3}{39}\)
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\(\dfrac{2}{8}=\dfrac{4}{16};\dfrac{7}{4}=\dfrac{28}{16}\)
\(\dfrac{28}{16}>\dfrac{9}{16}>\dfrac{4}{16}\rightarrow\dfrac{28}{16},\dfrac{9}{16},\dfrac{4}{16}\)