The article explores how private contributions can finance public projects efficiently. They found that the game involved in this process is cooperative and strategic, leading to equilibrium where no money is wasted. Players only contribute if all their necessary projects are realized. Strategies that maximize overall welfare are strong Nash equilibria. These equilibria correspond to core elements of the game, ensuring fair payoffs for all players. The study shows a direct link between strong Nash equilibria and core elements, maximizing the number of players with positive outcomes.