## 270. Math Puzzle 11/87

Off to mushroom hunting!

Carla and Stephan were blessed with collecting luck: The baskets filled to the brim with mushrooms were almost too heavy to carry home. Mushrooms, however, consist of 85 percent water. After they were dried, the mushrooms weighed 15 kilograms less than on the way home, as they now only contained 40 percent water.

How many kilograms of fresh mushrooms did the children collect?
The mushrooms lost 15 kg of mass. As a result, the water content decreased from 85 percent to 40 percent. Therefore, the mass loss corresponds to 45 percent of the fresh mushrooms.

$$
\frac{x \text{ kg mushrooms}}{100 \%}=\frac{15 \text{ kg mushrooms}}{85 \% - 40 \%} \quad, \quad x=33.3 \text{ kg}
$$

The children had collected $33.3 \text{ kg}$ of fresh mushrooms.