Answer 1

Christian Huml ,
there is a logical issue in your code. the task description says:
...
For children under 3 years of age, the ticket is free. (means < 3)
...
your code is:
...
if age>3:
...
what is if age is 3 years ?

Answer 2

Here in SL Paygroun you have to enter all input data at the start. For example:
1
2
3
4
5

Answer 3

Run this code :
https://code.sololearn.com/WhiNb9BkJUVC/?ref=app
see
Ex: need input of 5 integers 1 2 3 4 5
Input in multiple lines
1 (press enter)
2 (press enter)
3 "
4 ."
5 (press submit)
For reading by Read Line methods, it must. But other it works by space separating..
Hope it helps..

Answer 4

Solo Learn web codes interactive.
Except web, other languages playgrounds are not interactive.
Christian Huml
The above code explains it clearly...