Ok so I found the area of a rectangle.
A=lxw
A=(550) (350)
A=192,500
And the diameter is 50ft but I don’t know I look up videos it’s still not helping me.

  circle area = 1963.495 ft²

Step-by-step explanation:

Given

  A rectangle 550 ft by 350 ft packed with circles on a rectangular grid

Find

  the area of the largest circle that can be packed this way

Solution

The diameter of the circle must be a factor of both 350 and 550. We want the diameter to be the largest such factor. We can write the factors of 350 and 550 as ...

The largest factor common to both numbers is 50, so that will be the diameter of the largest circle that will fit on a square grid.

The area of a circle is commonly given by the formula ...

  A = πr² . . . . . where r represents the radius of the circle.

The radius is half the diameter, so will be (50 ft)/2 = 25 ft. And the area of the circle is ...

  A = π(25 ft)² = 625π ft² ≈ 1963.495 ft²

The area of one circle is about 1963.495 square feet.

The total number of circles is 11×7 = 77. Their total area is 77×1963.495 ft² ≈ 151,189 ft². This is 151,189/192,400 ≈ 78.54% of the total area of the rectangle.

i got 10.28 but that rounds up to 10.3

i think it would be 42cm