\(\dfrac{35}{210}=\dfrac{35:35}{210:35}=\dfrac{1}{6}\)
\(\dfrac{34}{68}=\dfrac{34:34}{68:34}=\dfrac{1}{2}\)
\(\dfrac{64}{720}=\dfrac{64:8}{720:8}=\dfrac{8}{90}\)
Lời giải:
$\frac{35}{210}=\frac{35}{35\times 6}=\frac{1}{6}$
$\frac{34}{68}=\frac{34}{34\times 2}=\frac{1}{2}$
$\frac{64}{720}=\frac{8\times 8}{8\times 90}=\frac{8}{90}=\frac{4\times 2}{2\times 45}=\frac{4}{45}$