The perimeter of the square was increased by 30%, how much percent will the area of the square increase?

Let us denote the perimeter of the original square through p.

Then the length of the side of this square will be p / 4, and the area of this square will be (p / 4) ^ 2 = p ^ 2/16.

If the perimeter of the original square is increased by 30%, then the perimeter of the resulting square will be p + (30/100) * p = p + 0.3p = 1.3p, the side length of the resulting square will be 1.3p / 4, and the area of the resulting square will be (1.3 p / 4) ^ 2 = 1.69 p ^ 2/16.

Therefore, the area of the original square will increase by:

100 * (1.69 p ^ 2/16 – p ^ 2/16) / (p ^ 2/16) = 100 * (0.69 p ^ 2/16) / (p ^ 2/16) = 100 * 0.69 = 69% …

Answer: the area of the original square will increase by 69%.