You should draw a picture to visualize the problem easier.
The circumference of inner circle = 44 ft
That means the radius of the inner circle:
2*pi*r = 44
r = 44/(2pi) = 22/pi
Using the picture you hopefully drew, we see that the radius of the outer circle:
22/pi + 2
To figure out the circumference of the outer circle:
2pi*(22/pi + 2) = 44 + 4pi
So how much bigger is the the circumference of the outer circle than the inner circle?
44 + 4pi - 44 = 4pi
It is 4pi bigger or 4 * (3.14) = 12.56 feet
it would obviously take 15 days if this answers your question
