60000 frtnyi tőke, ha 1 évvel rövidebb ideig kamatozott volna, a végösszeg 3996, 12 frttal kevesebb lett volna; ha pedig 1 évvel tovább kamatozik, 4156, 02 frttal többre növekedik. Hány \%-ra és hány évre volt a tőke elhelyezve?

60000 capital, if it had been interest-bearing for 1 year less, the final amount would have been 3996.12 less; if it had been interest-bearing for 1 year longer, it would have increased by 4156.02. At what percentage and for how many years was the capital placed?
Let the growth factor be denoted by $e$, then according to the problem:

$$
\begin{aligned}
& 60000 e^{n-1}=60000 e^{n}-3996.12 \\
& 60000 e^{n+1}=60000 e^{n}+4156.02
\end{aligned}
$$

from which:

$$
\begin{gathered}
60000 e^{n}\left(1-\frac{1}{e}\right)=3996.12 \\
60000 e^{n}(e-1)=4156.02
\end{gathered}
$$

dividing these two equations:

$$
e=\frac{4156.02}{3996.12}
$$

from which

$$
e=1.04 \text { and } p=4
$$

Substituting this value of $e$ into (2):

$$
2400 \cdot 1.04^{n}=4156.02
$$

from which

$$
n=14 \text { years. }
$$

(Géza Petrogalli, Beszterczebánya.)

Number of solutions: 36.