Tính biểu thức: 1/2 + 1/8 =

\(\frac{1}{2}\) + \(\frac{1}{8}\) = \(\frac{4}{8}\) + \(\frac{1}{8}\) = \(\frac{5}{8}\)

\(\frac{5}{{12}}\) – \(\frac{1}{3}\) = \(\frac{5}{{12}}\) – \(\frac{4}{{12}}\) = \(\frac{1}{{12}}\)

\(\frac{7}{{12}}\) × \(\frac{6}{{21}}\) = \(\frac{1}{6}\)

\(\frac{6}{{15}}\) : \(\frac{3}{{10}}\) = \(\frac{6}{{15}}\) × \(\frac{{10}}{3}\) = \(\frac{4}{3}\)