To find the cost of one shirt, you can divide the total cost by the quantity of shirts.
For example, let's consider the quantity of 6 shirts and its cost:
Cost for 6 shirts = $18
Cost for 1 shirt = Total Cost / Quantity = $18 / 6 = $3
You can also verify this with the other quantities:
- For 5 shirts: $15 / 5 = $3
- For 4 shirts: $12 / 4 = $3
- For 3 shirts: $9 / 3 = $3
In each case, the cost of one shirt is $3.