a.\(\frac{2}{5}\)+\(\frac{1}{2}\)+\(\frac{7}{10}\)=\(\frac{4}{10}\)+\(\frac{5}{10}\)+\(\frac{7}{10}\)=\(\frac{4+5+7}{10}\)=\(\frac{16}{10}\)=\(\frac{8}{5}\)
b.\(\frac{9}{20}\)-\(\frac{8}{15}\)x\(\frac{5}{12}\)=\(\frac{9}{20}\)-\(\frac{40}{180}\)=\(\frac{81}{180}\)-\(\frac{40}{180}\)=\(\frac{41}{180}\)
c.\(\left(8-\frac{4}{3}\right)\)x\(\left(\frac{5}{6}+\frac{17}{12}\right)\)=\(\frac{20}{3}\)x\(\frac{27}{12}\)=\(\frac{540}{36}\)=\(15\)
d.\(\frac{14}{3}\):\(\frac{3}{2}\)-\(\frac{4}{3}\)=\(\frac{28}{9}\)-\(\frac{4}{3}\)=\(\frac{28}{9}\)-\(\frac{12}{9}\)=\(\frac{14}{9}\)
