1. The problem states: Find the perimeter of a square with side length 12 cm. 2. The formula for the perimeter $P$ of a square with side length $s$ is: $$P = 4 \times s$$ 3. Substitute $s = 12$ cm into the formula: $$P = 4 \times 12$$ 4. Multiply: $$P = 48$$ 5. So, the perimeter of the square is 48 cm.