You can
put this solution on YOUR website! Assume you have a random sample of 8 people.
1. Find the probability that your sample has exactly 6 women.
2. Find the probability that you have at least 6 women.
3. What is the probability that there are at most 0 women.
4. Find the probability that there at least as many men as there are women
Look in the cumulative binomial probability table with n=8
and look at the column with p=.5.
You can find such a table here:
http://www.statisticshowto.com/tables/binomial-distribution-table/
You will see this. The values are really p(x ≦ the value listed)
although the heading just reads "x":
x≦ p=.5
-------
0 .004
1 .035
2 .145
3 .363
4 .637
5 .855
6 .965
7 .996
8 1
1. Find the probability that your sample has exactly 6 women.
p(x=6) = p(x≦6) - p(x≦5) = .965 - .855 = .110
2. Find the probability that you have at least 6 women.
p(x≧6) = p(x≦8) - p(x≦5) = 1 - .855 = .145
[Notice that that is the same as p(x≦2) because if there are at least
6 women there are 2 or fewer men, and the probability of a man and a
woman are the same.]
3. What is the probability that there are at most 0 women.
That's the same as p≦0 = .004
4. Find the probability that there at least as many men as there are women
That's the probability that there are 4 or fewer women.
p(x≦4) = .637
Edwin