2. Three generous friends, each of whom has candies, redistribute them as follows: Vasya gives some of his candies to Petya and Kolya, doubling the number of candies they have. After this, Petya gives some of his candies to Kolya and Vasya, doubling the number of candies they have as well. Finally, Kolya gives some of his candies to Vasya and Petya, doubling the number of candies they have again. It turns out that Kolya had 36 candies both at the beginning and at the end. How many candies do the boys have in total?
Answer: 252.

Let's track the number of candies Kolya has. After the first redistribution, he has 72, and after the second - 144. Therefore, he gave away $144-36=108$ candies, and during this time, the number of candies Vasya and Petya had doubled. So, the total number of candies Vasya, Petya, and Kolya have together is $2 \cdot 108+36=$ 252.

$\pm$ Correct reasoning with an arithmetic error leading to an incorrect answer. 5 points

- Correct answer without justification (an example is not considered justification). 1 point