\(a,\dfrac{1}{4},\dfrac{5}{6}và\dfrac{7}{12}\)
\(\dfrac{1}{4}=\dfrac{1\times3}{4\times3}=\dfrac{3}{12};\dfrac{5}{6}=\dfrac{5\times2}{6\times2}=\dfrac{10}{12};\dfrac{7}{12}\)
\(b,\dfrac{1}{9},\dfrac{3}{5},\dfrac{11}{45}\)
\(\dfrac{1}{9}=\dfrac{1\times5}{9\times5}=\dfrac{5}{45};\dfrac{3}{5}=\dfrac{3\times9}{5\times9}=\dfrac{27}{45};\dfrac{11}{45}\)