Question

Tính (theo mẫu):

a) \(\dfrac{2}{5}\times\dfrac{9}{8}\)                     \(\dfrac{10}{7}\times\dfrac{21}{20}\)                      \(6\times\dfrac{3}{4}\)                      \(\dfrac{9}{10}\times\dfrac{7}{3}\times\dfrac{5}{14}\)

b) \(\dfrac{6}{5}:\dfrac{9}{20}\)                     \(8:\dfrac{16}{5}\)                          \(\dfrac{21}{4}:7\)                       \(6\times\dfrac{1}{12}:\dfrac{6}{2}\)