Vojta started writing the number of the current school year in his notebook: 2019202020192020... and continued doing so indefinitely. When he wrote 2020 digits, he got bored and stopped.

How many twos did he write?

(L. Růžičková)

Hint. How many twos would Vojta write if he only wrote 20 digits?
The school year number 20192020 is eight digits long and contains three twos. Since $2020=8 \cdot 252+4$, Vojta wrote the entire number 20192020, 252 times, and on the remaining four places, the number 2019.

In total, Vojta wrote $252 \cdot 3+1=757$ twos.