To solve the inequality \( \frac{x}{13} < \frac{4}{5} \), we can multiply both sides by 13 (since 13 is positive, the inequality direction remains the same):
\[ x < 13 \cdot \frac{4}{5} \]
Calculating the right side:
\[ 13 \cdot \frac{4}{5} = \frac{52}{5} = 10.4 \]
So the inequality simplifies to:
\[ x < 10.4 \]
This means \( x \) is less than 10.4.
In terms of response options, \( x < 10 \frac{2}{5} \) is equivalent to \( x < 10.4 \).
Thus, the best response is:
x less than 10 Start Fraction 2 over 5 End Fraction.