\(B=\left(6-2\dfrac{4}{5}\right).3\dfrac{1}{8}-1\dfrac{3}{5}:\dfrac{1}{4}\)
\(B=\left(6-\dfrac{14}{5}\right).\dfrac{25}{8}-\dfrac{8}{5}:\dfrac{1}{4}\)
\(B=\left(\dfrac{30}{5}-\dfrac{14}{5}\right).\dfrac{25}{8}-\dfrac{8}{5}:\dfrac{1}{4}\)
\(B=\dfrac{16}{5}.\dfrac{25}{8}-\dfrac{8}{5}:\dfrac{1}{4}\)
\(B=10-\dfrac{32}{5}\)
\(B=\dfrac{50}{5}-\dfrac{32}{5}\)
\(B=\dfrac{18}{5}\)
\(B=\left(6-\dfrac{24}{5}\right).3\dfrac{1}{8}-1\dfrac{3}{5}:\dfrac{1}{4}\\ =\left(\dfrac{30}{5}-\dfrac{24}{5}\right).\dfrac{25}{8}-\dfrac{8}{5}:\dfrac{1}{4}\\ =\dfrac{6}{5}.\dfrac{25}{8}-\dfrac{32}{5}\\ =\dfrac{150}{40}-\dfrac{32}{5}\\ =\dfrac{75}{20}-\dfrac{128}{20}=\dfrac{-53}{20}\)
