\(\dfrac{28}{15}.\dfrac{1}{4^2}.3+\left(\dfrac{8}{15}-\dfrac{69}{60}.\dfrac{5}{23}\right):\dfrac{51}{54}\\ =\dfrac{28}{15}.\dfrac{1}{16}.3+\left(\dfrac{8}{15}-\dfrac{1}{4}\right):\dfrac{51}{54}\\ =\dfrac{7}{60}.3+\dfrac{17}{60}:\dfrac{51}{54}\\ =\dfrac{7}{20}+\dfrac{3}{10}\\ =\dfrac{13}{20}\)
\(\dfrac{28}{15}\times\dfrac{1}{4^2}\times3+\left(\dfrac{8}{15}-\dfrac{69}{60}\times\dfrac{5}{23}\right):\dfrac{51}{54}\)
\(=\dfrac{28}{15}\times\dfrac{1}{16}\times3+\left(\dfrac{8}{15}-\dfrac{1}{4}\right):\dfrac{51}{54}\)
\(=\dfrac{28}{15}\times\dfrac{1}{16}\times3+\left(\dfrac{32}{60}-\dfrac{15}{60}\right):\dfrac{51}{54}\)
\(=\dfrac{28}{15}\times\dfrac{1}{16}\times3+\dfrac{17}{60}:\dfrac{51}{54}\)
\(=\dfrac{28}{15}\times\dfrac{1}{16}\times3+\dfrac{17}{60}\times\dfrac{54}{51}\)
\(=\dfrac{7}{60}\times3+\dfrac{17}{60}\times\dfrac{54}{51}\)
\(=\dfrac{7}{20}+\dfrac{17}{60}\times\dfrac{54}{51}\)
\(=\dfrac{7}{20}+\dfrac{3}{10}\)
\(=\dfrac{7}{20}+\dfrac{6}{20}\)
\(=\dfrac{13}{20}\)
\(\dfrac{28}{15}\cdot\dfrac{1}{4^2}\cdot3+\left(\dfrac{8}{15}-\dfrac{69}{60}\cdot\dfrac{5}{23}\right):\dfrac{51}{54}\\ =\dfrac{7}{5}\cdot\dfrac{1}{4}+\left(\dfrac{8}{15}-\dfrac{3}{6}\right)\cdot\dfrac{54}{51}\\ =\dfrac{7}{20}+\dfrac{1}{30}\cdot\dfrac{54}{51}\\ =\dfrac{7}{20}+\dfrac{3}{85}\\ =\dfrac{131}{340}\)
