One hundred business people gather at a meeting. 85 of them carry a cellular phone, 80 of them have a beeper, 75 of them speak at least two languages and 70 of them wear a suit. Therefore, a certain number of them have all of the above: a cell phone AND a beeper AND speak at least two languages AND wear a suit.
Out of these 100 businesspeople, what is the least possible number who have all of the above?