\(\dfrac{7}{13}.\dfrac{5}{19}+\dfrac{7}{19}.\dfrac{14}{13}+\dfrac{6}{13}\)
= \(\dfrac{7}{13}\left(\dfrac{5}{19}+\dfrac{14}{19}\right)+\dfrac{6}{13}\)
= \(\dfrac{7}{13}+\dfrac{6}{13}=1\)
\(\dfrac{7}{13}\cdot\dfrac{5}{19}+\dfrac{7}{19}\cdot\dfrac{14}{13}+\dfrac{6}{13}\)
\(=\dfrac{7}{13}\cdot\left(\dfrac{5}{19}+\dfrac{14}{19}\right)+\dfrac{6}{13}\)
\(=\dfrac{7}{13}+\dfrac{6}{13}\)
\(=1\)
\(\dfrac{7}{13}.\dfrac{5}{19}+\dfrac{7}{19}.\dfrac{14}{13}+\dfrac{6}{13}\)
\(=\dfrac{7}{13}.\dfrac{5}{19}+\dfrac{7}{13}.\dfrac{14}{19}+\dfrac{6}{13}\)
\(=\dfrac{7}{13}.\left(\dfrac{5}{19}+\dfrac{14}{19}\right)+\dfrac{6}{13}\)
\(=\dfrac{7}{13}.1+\dfrac{6}{13}\)
\(=\dfrac{7}{13}+\dfrac{6}{13}\)
\(=1\)
