Question

The intensity of a radio signal from the radio station varies inversely as the square of the distance from the station. suppose intensity is 8000 units at a distance of 2 miles. what will the intensity be at a distance of 11 miles? round your answer to the nearest unit.

Answer 1

Let I represent intensity and and d the distance;
I$\alpha \frac{1}{ d^{2} }$
When I=8000
8000=$\frac{k}{4}$
k=32000
I=$\frac{32000}{d}$
I=$\frac{32000}{121}$
I=265 units