Tính phép tính 2/5 + 1/ 10 4/ 13 x 26/16

\(\frac{2}{5}\) + \(\frac{1}{{10}}\) = ……………………………

\(\frac{3}{{15}}\) – \(\frac{1}{{45}}\) = ……………………………

\(\frac{4}{{13}}\) × \(\frac{{26}}{{16}}\) = ……………………………

\(\frac{7}{2}\) : \(\frac{{21}}{8}\) = ………………………………