To represent the situation as an inequality, we can start by letting \( s \) represent the number of shirts Demetrius can buy. Each shirt costs $16, so the total cost for \( s \) shirts can be expressed as \( 16s \).
Demetrius can spend as much as $50, which leads us to the inequality:
\[ 16s \leq 50 \]
This inequality means that the total cost of the shirts \( (16s) \) must be less than or equal to $50.