A national center for health statistics report based on 1985 data states 30% of american adults smoke. Consider a simple random sample of 15 adults selected at that time. Find the probability that the number of smokers in the sample would be.
A) three?
B)More then 5 but less then 10?
2007-02-24 06:23:19 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
This can be solved as a binomial distribution problem.
p=.3, n=15, find P(x=3)=
(15C3)*(.3^3)*(.7^12)
For second part, repeat for P(x=6), P(x=7), P(x=8), P(x=9).
2007-02-24 06:39:59 · answer #1 · answered by fcas80 7 · 0⤊ 0⤋
its binomial distribution that u have to use. where p=30%=0.3 i.e u assume that in any random sample of n people from the american population the probality that 1 person smokes is 30%.
so your randomm variable say X(# of ppl who somke in sample) is distributed b(n,p) where n in this case is 15 and p=.3)
2007-02-24 15:09:28 · answer #2 · answered by hiphop 2 · 0⤊ 0⤋
You do 0.30 (30% is 0.30) times 15. You get 4.5 but...you decide the best answer.
2007-02-24 14:28:55 · answer #3 · answered by Ale 2 · 0⤊ 0⤋