Problem 2. The sum of three natural numbers is 2015. Find the three numbers, knowing that if we add 11 to the first, subtract 11 from the second, and divide the third number by 11, we get the same number each time.
Solution. Let a, b, c be the three natural numbers.

## 1p for free

$$
\begin{aligned}
& a+b+c=2015 \\
& a+11=x \rightarrow a=x-11 \\
& b-11=x \rightarrow b=x+11 \\
& c: 11=x \rightarrow c=11 x
\end{aligned}
$$

Substituting into the first relation, we get:

$$
x-11+x+11+11 x=2015
$$

$13 x=2015$

$x=155$

Finalization: $a=144, b=166, c=1705$.