What is the Least common Denominator (LCD) of 7/8 and 1/6?

The least common multiple of $6$ and $8$ is $24$. Hence:
$\setminus \frac{7}{8} + \setminus \frac{1}{6} = \setminus \frac{7 \setminus \cdot 3}{8 \setminus \cdot 3} + \setminus \frac{1 \setminus \cdot 4}{6 \setminus \cdot 4} = \setminus \frac{21}{24} + \setminus \frac{4}{24} = \setminus \frac{25}{24}$