Rút gọn rồi tính

a) \(\frac{6}{{14}} + \frac{2}{7} = ............................\)

b) \(\frac{8}{{12}} + \frac{2}{3} = ............................\)

\(\frac{7}{5} - \frac{3}{7} = .....................\)

\(\frac{5}{4} - \frac{1}{6} = .....................\)

\(\frac{7}{8} - \frac{1}{4} = .....................\)

\(\frac{{12}}{{14}} - \frac{3}{7} = .....................\)

a)\(\frac{{12}}{{25}} + \frac{7}{{25}} + \frac{8}{{25}}\)

= ……………………

= ……………………

b) \(\frac{5}{{13}} + \frac{6}{{13}} + \frac{4}{{13}}\)

= ……………………

= ……………………

\(\frac{4}{7} + \frac{{.....}}{{.....}} = 1\)

\(\frac{2}{5} + \frac{{.....}}{{.....}} = 1\)

\(\frac{1}{3} + \frac{{.....}}{{.....}} = 1\)

\(\frac{6}{{11}} + \frac{{.....}}{{.....}} = 1\)

\(\frac{5}{9} + \frac{{.....}}{{.....}} = 1\)

\(\frac{1}{6} + \frac{{.....}}{{.....}} = 1\)

a)\(\frac{3}{{10}} + \frac{{.....}}{{10}} = \frac{7}{{10}}\)

b)\(\frac{9}{6} + \frac{3}{{.....}} = \frac{{11}}{6}\)

c)\(\frac{{13}}{{23}} + \frac{8}{{23}} = \frac{{21}}{{.....}}\)