Find the perimeter of the 15 cm square, reduce each side by 6 cm and find the perimeter of the new square.

The perimeter of a square is calculated using the formula:
P = 4 * a where P is the perimeter of the square, and is the side of the square.

The side of the first square is 15 cm, so its perimeter is 60 cm.
1) P₁ = 4 * a = 4 * 15 = 60 (cm) perimeter of the first square.

The side of the first square is 15 cm, and the side of the new square is 6 cm less, which means it is 9 cm.
2) 15 – 6 = 9 (cm) side of the new square.

The side of the new square is 9 cm, which means that the perimeter of the new square is 36 cm.
3) P₂ = 4 * a = 4 * 9 = 36 (cm) perimeter of the new square.