a) \(4-\dfrac{2}{3}-\dfrac{10}{24}\)\(=\dfrac{12}{3}-\dfrac{2}{3}-\dfrac{10}{24}\)\(=\dfrac{10}{3}-\dfrac{10}{24}=\dfrac{80}{24}-\dfrac{10}{24}=\dfrac{70}{24}=\dfrac{35}{12}\)
b) \(\dfrac{12}{7}\) x \(\dfrac{3}{4}:\dfrac{3}{14}\)
\(=\dfrac{12}{7}\) x\(\dfrac{3}{4}\) x \(\dfrac{14}{3}\)\(=\dfrac{9}{7}\) x \(\dfrac{14}{3}\)\(=\dfrac{126}{21}=6\)
c) \(2+\dfrac{5}{2}:18\)
\(=\dfrac{4}{2}+\dfrac{5}{2}:18\)
\(=\dfrac{9}{2}\) x \(\dfrac{1}{18}=\dfrac{9}{36}=\dfrac{1}{4}\)