Answer:
The radius of the town is 3.641 km.
Explanation:
The density of people in the city is given by the formula:
density = number of people / area of the city
Since the city is a perfect circle, it's area is given by:
area of the city = pi*r²
We have:
480 = 20000/pi*r²
480*pi*r² = 20000
r² = 20000/480*pi
r = sqrt(20000/480*pi) = 3.641
The radius of the town is 3.641 km.