## Elementary Algebra

$= -\frac{n}{10}$
1) Put $n$ in the numerators of the fractions. 2) Find a common denominator: Multiply the first fraction by $6$, the second fraction by $10$ and the third fraction by $5$ to obtain a common denominator of $30$ $\frac{2}{5}n + \frac{1}{3}n - \frac{5}{6}n$ $= \frac{2n}{5} + \frac{n}{3} - \frac{5n}{6}$ $= \frac{2n(6)}{30} + \frac{n(10)}{30} - \frac{5n(5)}{30}$ $= \frac{12n}{30} + \frac{10n}{30} - \frac{25n}{30}$ $= \frac{12n+10n-25n}{30}$ $= \frac{22n-25n}{30}$ $= -\frac{3n}{30}$ (Simplify $\frac{3}{30} = \frac{1}{10}$) $= -\frac{(1)n}{10}$ $= -\frac{n}{10}$