Bài 2:

a) 

 \(\frac{2}{5}\) + \(\frac{3}{10}\) - \(\frac{1}{2}\)  = \(\frac{4}{10}\) + \(\frac{3}{10}\) - \(\frac{5}{10}\) = \(\frac{7}{10}\) - \(\frac{5}{10}\) = \(\frac{2}{10}\) = \(\frac{1}{5}\)

b)

 \(\frac{8}{11}\) + \(\frac{8}{33}\) x \(\frac{3}{4}\) = \(\frac{8}{11}\) + \(\frac{2}{11}\) = \(\frac{10}{11}\)

c)

 \(\frac{7}{9}\) x \(\frac{3}{14}\) : \(\frac{5}{8}\)  = \(\frac{1}{6}\) : \(\frac{5}{8}\) = \(\frac{1}{6}\) x \(\frac{8}{5}\) = \(\frac{8}{30}\) = \(\frac{4}{15}\)

d)

 \(\frac{5}{12}\) - \(\frac{7}{32}\) : \(\frac{21}{16}\)  = \(\frac{5}{12}\) - \(\frac{7}{32}\) x \(\frac{16}{21}\) = \(\frac{5}{12}\) - \(\frac{1}{6}\) = \(\frac{5}{12}\) - \(\frac{2}{12}\) = \(\frac{3}{12}\)