a.Ta có:
\(\dfrac{14}{18}=\dfrac{7}{9}=\dfrac{7\times5}{9\times5}=\dfrac{35}{45}\)
\(\dfrac{21}{35}=\dfrac{3}{5}=\dfrac{3\times9}{5\times9}=\dfrac{27}{45}\)
\(\Rightarrow\dfrac{14}{18}>\dfrac{21}{35}\)
14/8 = 35/45 , 21/35 = 27/45
nên 14/18>21/35
(HT)