\(\dfrac{25.9-25.17}{-8.80-8.10}=\dfrac{-200}{-720}=\dfrac{5}{18}\)
\(\dfrac{48.12-48.15}{-3.270-3.30}=\dfrac{-144}{-900}=\dfrac{4}{25}\)
a, Quy đồng
\(\dfrac{5}{18}=\dfrac{5\times25}{18\times25}=\dfrac{125}{450}\)
\(\dfrac{4}{25}=\dfrac{4.18}{25.18}=\dfrac{72}{450}\)