A circular swimming pool has a radius of 20 feet of fence is going to be built So that there is a 4 foot space around the entire pool what is the length of the fence Cynthia solve the problem as shown what was her error

The length of the fence is 45.09ft

Step-by-step explanation:

To solve this exercise we first have to calculate the radius of the pool and then add the 4 foot we want to distance it.

r = radius

π = 3.14

c =  circumference = 20ft

c = π * 2r

we clear r

r = c / 2π

now we replace the values we know

r = 20ft / 2 * 3.14

r = 3.18ft

now we add the 4 feet we want away

3.18ft + 4ft = 7.18ft

r = 7.18ft

c2 = π * 2r

c2 = 3.14 * 2 * 7.18

c2 = 45.09ft

The length of the fence is 45.09ft