I think it’s about 134.13 ft
to find the circle the formula is pi times the radius squared so:
12.5 x 12.5 = 156.25
156.25 x pi ≈ 490.8738 ft squared
to find the square it’s base x height so:
25 x 25 = 625
then to find the shaded part you just find the difference:
625 - 490.87 = 134.13 ft
