Find the diameter of a circle with an area of 615.75 square centimeters

Area of a circle formula:

[tex]A = \pi r^{2} [/tex]

You're given that A = 615.75, so:

[tex]615.75 = \pi r^{2} [/tex]

Solve for r:

[tex]r = \sqrt{(615.75/ \pi )} r = 14 cm[/tex]

Diameter is equal to twice the radius, so doubling 14 gives you
[tex]d = 28cm[/tex]