SOLUTION: In the last presidential election 39% of the registerd voters in a certain city actually cast ballots. a)In a random sample of 20 voters from that city, what is the probability th

Algebra ->  Probability-and-statistics -> SOLUTION: In the last presidential election 39% of the registerd voters in a certain city actually cast ballots. a)In a random sample of 20 voters from that city, what is the probability th      Log On


   



Question 374880: In the last presidential election 39% of the registerd voters in a certain city actually cast ballots.
a)In a random sample of 20 voters from that city, what is the probability that exactly 8 voted in the last presidential election?

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
Let x=.39 and y=.61
(x+y)^20
nCr=Combination=n!/((n-r)!r!
.
20C8=125970
125970*x^8*y^12=0.179 the probability that exactly 8 voted.
.
Ed