SOLUTION: In a recent election there were 1000 eligible voters. They were asked to vote on two issues, A and B. The results were as follows: 150 people voted for A, 400 people voted for B, a

Algebra ->  Probability-and-statistics -> SOLUTION: In a recent election there were 1000 eligible voters. They were asked to vote on two issues, A and B. The results were as follows: 150 people voted for A, 400 people voted for B, a      Log On


   

Question 1033425: In a recent election there were 1000 eligible voters. They were asked to vote on two issues, A and B. The results were as follows: 150 people voted for A, 400 people voted for B, and 50 people voted for A and B. If one person is chosen at random from the 1000 eligible voters, find the following probabilities:
The person voted for A, given that he voted for B.
The person voted for B, given that he voted for A.
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
The intersection is 50.
Given that somebody voted for B (400) the probability they voted for A is 1/8.
So if that a person voted for A (150 total), 50 of them voted for B, since 50 voted for both. That probability is 1/3.