SOLUTION: okay i have a table with the drinking habits of students and one of my questions is if two different students are chosen at random, find the probability that they both are heavy dr

Question 765802: okay i have a table with the drinking habits of students and one of my questions is if two different students are chosen at random, find the probability that they both are heavy drinkers. does that mean i have to find the probability that one is a heavy drinker and then double it or? i dont need you to solve the problem for me and i dont think you need to know the values i just want to know the formula or the procedure for solving it, can you help me please
Answer by rothauserc(4718) (Show Source): You can put this solution on YOUR website!
say there are n students and x of them are heavy drinkers
the probability that the first chosen student is a heavy drinker is x/n
the probability that the second chosen student is a heavy drinker is x-1 / n-1
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the probability that both students chosen are heavy drinkers is:
(x/n) * (x-1 / n-1)

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