what equation can represent the problem: The cost of a shirt is $24, and the cost of a pair of shoes is three times the cost of the shirt. What is the cost of the pair of shoes?
Let the cost of the shirt be represented by the variable "s".
The cost of the pair of shoes is three times the cost of the shirt, so it can be represented by the expression "3s".
Given that the cost of the shirt is $24, we have s = $24.
Therefore, the cost of the pair of shoes is 3s = 3($24) = $72. Answer: \boxed{72}.