Summary

My client plays 5v5 online game and desperately needs to win.

He is teamed with 4 randomly chosen online teammates and is able to view their historical performance before the game starts.

Given the statistics of the teammates, what is the probabilty of winning the game?

If his chance is 'low', he wants to leave the team and group with another set of teammates.

Calculate the probability of winning before the game starts and evaluate whether the client should play or leave the game.