Of the 232 airports available for public use in Themeliville, 121 are paved and lighted. For a simple random sample of 50, what is the probability that between 27 and 31 of the airports in the sample will be paved and lighted?

1 Answer
Aug 18, 2016

#39.17#

Explanation:

so we have the probability of being lighted as

#p(L) = 121/232#

this can be modeled using the binomial cumulative distribution thus

#p(27<=L<=31) = sum_(k=27)^31( ""_nC_k) p(L)^k (1-p(L))^(n-k)# where #n=50#

#p(27<=L<=31) =39.17#