[tex] \frac{5}{6} [/tex] + [tex] \frac{7}{8} [/tex]
Convert your denominators into a same number..
[tex] \frac{20}{24} ~+~ \frac{21}{24} ~=~ \frac{41}{24} [/tex]
[tex] \frac{41}{24} [/tex] as a mixed number = [tex]1 \frac{17}{24} [/tex]
Your answer - [tex]1 \frac{17}{24} [/tex]