a ) 4 - \(1\dfrac{4}{5}\).\(\dfrac{-3}{4}\) = 4 - \(\dfrac{-3}{5}\)= \(\dfrac{23}{5}\)
b) \(\dfrac{1}{7}.2\dfrac{1}{3}+\dfrac{5}{2}:\dfrac{3}{7}-\dfrac{59}{6}.\dfrac{1}{7}\)
\(\dfrac{1}{7}.\dfrac{7}{3}+\dfrac{5}{2}:\dfrac{3}{7}-\dfrac{59}{6}\cdot\dfrac{1}{7}\)
\(\dfrac{1}{7}\cdot\left(\dfrac{7}{3}-\dfrac{59}{6}\right)+\dfrac{35}{6}\)
\(\dfrac{1}{7}\cdot\dfrac{-15}{2}+\dfrac{35}{6}=\dfrac{-15}{14}+\dfrac{35}{6}=\dfrac{100}{21}\)
\(a,4-1\dfrac{5}{7}.\left(-0,75\right)\) = \(4-\dfrac{12}{7}.\dfrac{-75}{100}\) = \(4-\dfrac{12}{7}.\dfrac{3}{4}\)
=\(4-\dfrac{36}{28}=4-\dfrac{9}{7}=\dfrac{28}{7}-\dfrac{9}{7}=\dfrac{19}{7}\)
b, \(\dfrac{1}{7}.2\dfrac{1}{3}+\dfrac{5}{2}:\dfrac{3}{7}-\dfrac{59}{6}.\dfrac{1}{7}\) \(=\dfrac{1}{7}.\dfrac{7}{3}+\dfrac{5}{2}.\dfrac{7}{3}-\dfrac{59}{6}.\dfrac{1}{7}=\dfrac{7}{3}.\left(\dfrac{1}{7}+\dfrac{5}{2}\right)-\dfrac{59}{6}.\dfrac{1}{7}\)
=\(\dfrac{7}{3}.\left(\dfrac{2}{14}+\dfrac{35}{14}\right)-\dfrac{59}{42}=\dfrac{7}{3}.\dfrac{37}{14}-\dfrac{59}{42}\)
= \(\dfrac{1.37}{3.2}-\dfrac{59}{42}=\dfrac{37}{6}-\dfrac{59}{42}=\dfrac{259}{42}-\dfrac{59}{42}=\dfrac{200}{42}=\dfrac{100}{21}\)
