A point source emits sound equally in all directions in a non-absorbing medium. Two points $\mathrm{P}$ and $\mathrm{Q}$ are at a distance of $2 \mathrm{m}$ and $3 \mathrm{m}$ respectively from the source. The ratio of the intensities of the waves at $\mathrm{P}$ and $\mathrm{Q}$ is