To represent the situation where Demetrius can spend as much as $50 on shirts that cost $16 each, we can set up the following inequality:
Let \( s \) be the number of shirts he buys. The total cost for \( s \) shirts is given by the expression \( 16s \).
Since Demetrius can spend up to $50, we can write the inequality as:
\[ 16s \leq 50 \]
This inequality states that the total cost of the shirts (\( 16s \)) must be less than or equal to $50.