Algorithm for lottery with random and some criteria have a percentage value over the lottery

I've searched and end up in frustration i need algorithm for assigning room certain peoples randomly while considering their choice

just to describe it easily and precisely i need to make algorithm that can place user to specified dept according to their choice - people choose their room in top 10 list - people with higher age gets advantage of 20% - people in affirmative action* will have advantage of 30% sorry for my english