a,Sắp xếp: \(\dfrac{8}{45};\dfrac{4}{15};\dfrac{7}{15};\dfrac{3}{5}\)
b,Sắp xếp:\(\dfrac{3}{8};\dfrac{4}{5};\dfrac{47}{40};\dfrac{9}{4}\)
a: \(\dfrac{4}{15}=\dfrac{12}{45}\)
\(\dfrac{3}{5}=\dfrac{27}{45}\)
\(\dfrac{8}{45}=\dfrac{8}{45}\)
\(\dfrac{7}{15}=\dfrac{21}{45}\)
Do đó: \(\dfrac{8}{45}< \dfrac{4}{15}< \dfrac{7}{15}< \dfrac{3}{5}\)