\(\dfrac{1}{2}+\dfrac{1}{3}-\dfrac{1}{5}\)
\(=\dfrac{3}{6}+\dfrac{2}{6}-\dfrac{1}{5}\)
\(=\dfrac{5}{6}-\dfrac{1}{5}\)
\(=\dfrac{25}{30}-\dfrac{6}{30}\)
\(=\dfrac{19}{30}\)
\(\dfrac{1}{5}:4+\dfrac{3}{4}\)
\(=\dfrac{1}{5}\) x \(\dfrac{1}{4}+\dfrac{3}{4}\)
\(=\dfrac{1}{20}+\dfrac{3}{4}\)
\(=\dfrac{1}{20}+\dfrac{15}{20}\)
\(=\dfrac{4}{5}\)
\(\dfrac{4}{3}\) x \(\dfrac{9}{5}-\dfrac{3}{10}\)
\(=\dfrac{12}{5}-\dfrac{3}{10}\)
\(=\dfrac{24}{10}-\dfrac{3}{10}\)
\(=\dfrac{21}{10}\)
\(\dfrac{15}{14}:\dfrac{10}{21}\) x \(\dfrac{1}{5}\)
\(=\dfrac{15}{14}\) x \(\dfrac{21}{10}\) x \(\dfrac{1}{5}\)
\(=\dfrac{9}{4}\) x \(\dfrac{1}{5}\)
\(=\dfrac{9}{20}\)