# How do you add (5n)/3 + (4n)/3?

$\frac{5 n}{3} + \frac{4 n}{3} = 3 n$
$\frac{5 n}{3} + \frac{4 n}{3} = \frac{5 n + 4 n}{3} = \frac{\left(5 + 4\right) n}{3} = \frac{9 n}{3} = \frac{3 \cdot 3 n}{3} = 3 n$