Tính

a) \(\frac{2}{3} + \frac{4}{5} = \frac{{10}}{{15}} + \frac{{12}}{{15}} = \frac{{10 + 12}}{{15}} = \frac{{22}}{{15}}\)

b) \(\frac{7}{5} - \frac{4}{{20}} = \frac{{28}}{{20}} - \frac{4}{{20}} = \frac{{28 - 4}}{{20}} = \frac{{24}}{{20}} = \frac{6}{5}\)

c) \(\frac{3}{4} + 2 - \frac{1}{3} = \frac{3}{4} + \frac{2}{1} - \frac{1}{3} = \frac{9}{{12}} + \frac{{24}}{{12}} - \frac{4}{{12}} = \frac{{9 + 24 - 4}}{{12}} = \frac{{29}}{{12}}\)

d) \(4 - \frac{4}{5} = \frac{4}{1} - \frac{4}{5} = \frac{{20}}{5} - \frac{4}{5} = \frac{{20 - 4}}{5} = \frac{{16}}{5}\)