To solve the proportion equation, we need to first convert the mixed numbers into improper fractions. Then, we can set up the equation in terms of \( n \) and solve for \( n \) by cross-multiplying and simplifying the resulting equation.
Step 1: Convert Mixed Numbers to Improper Fractions
We start by converting the mixed numbers into improper fractions:
\[
6 \frac{2}{5} = \frac{32}{5}, \quad 11 \frac{1}{2} = \frac{23}{2}, \quad 9 \frac{1}{4} = \frac{37}{4}
\]
Step 2: Set Up the Proportion
The proportion can be expressed as:
\[
\frac{6 \frac{2}{5}}{11 \frac{1}{2}} = \frac{9 \frac{1}{4}}{n}
\]
Substituting the improper fractions, we have:
\[
\frac{\frac{32}{5}}{\frac{23}{2}} = \frac{\frac{37}{4}}{n}
\]
Step 3: Solve for \( n \)
Cross-multiplying gives us:
\[
32 \cdot 2 \cdot n = 37 \cdot 5 \cdot 23
\]
This simplifies to:
\[
64n = 4255
\]
Thus, solving for \( n \):
\[
n = \frac{4255}{64}
\]
Final Answer
The value of \( n \) is
\[
\boxed{n = \frac{4255}{256}}
\]