To determine the value of \( n \) that makes the ratios equivalent in the equation
\[ \frac{5}{4} = \frac{30}{n}, \]
you can cross-multiply to solve for \( n \):
\[ 5n = 30 \times 4. \]
Calculating the right side:
\[ 30 \times 4 = 120. \]
Now the equation is:
\[ 5n = 120. \]
Next, divide both sides by 5 to isolate \( n \):
\[ n = \frac{120}{5} = 24. \]
Therefore, the value of \( n \) is
\[ \boxed{24}. \]