The perimeter of a square with a side length of 7.85 cm is equal to that of a circle, which has an area of () square cm What do you want to fill in the brackets? Can the kind man tell me?

The perimeter of a square with a side length of 7.85 cm is equal to that of a circle, which has an area of () square cm What do you want to fill in the brackets? Can the kind man tell me?

seventy-eight point five