\(\dfrac{11}{31}\) và \(\dfrac{111}{311}\)
\(\dfrac{11}{31}\) = \(\dfrac{11\times10}{31\times10}\) = \(\dfrac{110}{310}\) = 1 - \(\dfrac{200}{310}\)
\(\dfrac{111}{311}\) = 1 - \(\dfrac{200}{311}\)
Vì \(\dfrac{200}{310}\) > \(\dfrac{200}{311}\)
Nên \(\dfrac{11}{31}\) < \(\dfrac{111}{311}\)
\(\dfrac{11}{31}=\dfrac{11x311}{31x311}=\dfrac{3421}{31x311}\)
\(\dfrac{111}{311}=\dfrac{111x31}{31x311}=\dfrac{3441}{31x311}\)
mà \(\dfrac{3421}{31x311}< \dfrac{3441}{31x311}\)
\(\Rightarrow\dfrac{11}{31}< \dfrac{111}{311}\)