$A$ and $B$ are traders who sold a certain fabric at different prices, and they both earned 85 crowns. $A$ sold 5 meters more than $B$. If $A$ sold the fabric at the same price as $B$, they would earn 60 crowns, and if $B$ sold the fabric at the same price as $A$, their revenue would be $30 \mathrm{~K}$. How many meters of fabric did each sell?
$A$ sold $x \mathrm{~m}-\mathrm{t}, B$ sold $x-5 \mathrm{~m}-\mathrm{t} ; B$ sold the meter of fabric for $\frac{60}{x}, A \mathrm{~m}$ for $\frac{30}{x-5}$ K-value. Thus:

$$
(x-5) \cdot \frac{60}{x}+x \cdot \frac{30}{x-5}=85
$$

or

$$
x^{2}-35 x+300=0
$$

from which

$$
x_{1}=20, x_{2}=15
$$

Therefore, $A$ sold $20 \mathrm{mt}, B$ sold 15, or $A$ sold $15 \mathrm{~m}-\mathrm{t}, B$ sold 10.

(Raab Rezsö, VII. o. t. Györ.)

Number of solutions: 26.