Question

About 1.15 million people live in a circular region with a population density of 18075 people per kilometer. Find the radius of the region

Answer 1

r = 5 km

Explanation:

Given that,

The population in a circular region = 1.15 million

The population density of the region = 18075 people per kilometer

We need to find the radius of the region.

We can find the area of circular region i.e.

`A=(P)/(d)\\\\A=(1.15* 10^6)/(18075 )\\A=63.6\ km^2`

We know that the area of a circular region is given by :

`A=\pi r^2\\\\\pi r^2=63.6\\\\r=\sqrt{(63.6)/(\pi)} \\\\r=4.49\ km`

or

r = 5 km

So, the radius of the region is equal to 5 km.