Question

An audio speaker producing a steady sound at an outdoor concert is 18 ft away from you. If you move to a position where the speaker is 67 ft distant, by what factor will the amplitude of the sound change?

Answer 1

The  amplitude of the sound is inversely proportional to the distance

$$A\sim\frac{1}{r}$$

Hence

$$\frac{A_2}{A_1}=\frac{r_1}{r_2}=\frac{18}{67}=0.27$$

Answer: 0.27