Elementary Algebra

$\frac{-13}{30n}$.
In order to add or subtract fractions, we start by making a common denominator (bottom of the fraction). Thus, we multiply 3/10n by 3/3 and 11/15n by 2/2 to obtain: $\frac{9}{30n}$-($\frac{22}{30n}$)=$\frac{-13}{30n}$.