# How do you add \frac { - 1} { 8d } + \frac { 7} { 6d }?

May 2, 2017

See the solution process below:

#### Explanation:

To add two fractions they must be over a common denominator. For this problem the Lowest Common Denominator is $24 d$. Therefore, before adding we must multiply each fraction by the appropriate form of $1$ to put them each over this common denominator:

$\left(\frac{3}{3} \times - \frac{1}{8 d}\right) + \left(\frac{4}{4} \times \frac{7}{6 d}\right) \implies \left(\frac{3 \times - 1}{3 \times 8 d}\right) + \left(\frac{4 \times 7}{4 \times 6 d}\right)$

$\implies - \frac{3}{24 d} + \frac{28}{24 d}$

We can now add the numerators over the common denominators:

$- \frac{3}{24 d} + \frac{28}{24 d} \implies \frac{- 3 + 28}{24 d} \implies \frac{25}{24 d}$