Question

A circular region has a population of about 15,500 people and a population density of about 775 people per square kilometer. Find the radius of the region. Round your answer to the nearest tenth. I got 1.4, but the answer is 2.5. Can anyone tell me how the rough steps? My brainly hurts .....

Answer 1

Answer:

2.5 km

Step-by-step explanation:

First, find the area of the region:

• A circular region has a population of about 15,500 people;
• A population density of about 775 people per square kilometer.

So, there are $15,500 :775=20$ square kilometers.

Now, let x kilometers be the radius of the circular region, then

$A_{\text{circilar region}}=\pi r^2\\ \\20=\pi r^2\\ \\r^2=\dfrac{20}{\pi}\approx 6.366198\\ \\r=\sqrt{3.366198}\approx 2.523$

To the nearest tenth this is 2.5 km.