3.7 Two parks with a total area of 110 hectares are divided into an equal number of plots. The plots of each park are equal in area to each other, but differ from those of the other park. If the first park were divided into plots of the same area as the second, it would have 75 plots, and if the second park were divided into plots of the same area as the first, it would contain 108 plots. Determine the area of each park.

## Geometric and Physical Problems
3.7 Let $S$ be the area of the park, $n$ be the number of equal-sized plots, and $Q$ be the area of a plot. Then $\frac{S}{n}=Q$. We will fill in the table with the given and required values in the sequence indicated by the numbers (2) and (12).

| Park | Initially |  |  | With new arrangement |  |  |
| :---: | :---: | :---: | :---: | :---: | :---: | :---: |
|  | $\underline{s}$ | $n$ | $Q$ | $S$ | $\bar{n}$ | $\ell$ |
| First | $7^{x}$ | (11) $\frac{108 x}{110-x}$ | $\frac{110-x}{9108}$ | (1) ${ }^{x}$ | $33^{75}$ | (5) $\frac{x}{75}$ |
| Second | 811 | $\frac{75(110-x)}{12)}$ | (10) $\frac{x}{75}$ | $\left(2^{10-x}\right.$ | (4) | $\frac{110-x}{6)}$ |

According to the condition,

$\frac{108 x}{110-x}=\frac{75(110-x)}{x}$,

from which $x=50$.

Answer: 50 and 60 hectares.