In one of the book fairs, they sold tickets for money to be given to the mujaahideen, and those who answered a question correctly were entered into a draw to be given prizes bought from the dealers who were taking part in the exhibition.
Praise be to Allaah.
We put this question to Shaykh ‘Abd al-‘Azeez
ibn Baaz (may Allaah have mercy on him), who answered:
is not permissible, because the way in which it is done is haraam.
Islam Q&A - Sheikh Muhammed Salih Al-Munajjid