Tính: 5/3 + 2/5

a) \(\frac{5}{3} + \frac{2}{5} = \frac{{25}}{{15}} + \frac{6}{{15}} = \frac{{31}}{{15}}\)

\(\frac{5}{7} + \frac{9}{{14}} = \frac{{10}}{{14}} + \frac{9}{{14}} = \frac{{19}}{{14}}\)

b)\(\frac{7}{3} - \frac{1}{4} = \frac{{28}}{{12}} - \frac{3}{{12}} = \frac{{25}}{{12}}\)

\(\frac{9}{{10}} - \frac{3}{4} = \frac{{18}}{{20}} - \frac{{15}}{{20}} = \frac{3}{{20}}\)