Question 1205803
this looks like a binomial probability distribution type of problem.


the formula is p(x) = p^x * q^(n-x) * c(n,x).


n is 15
x is from 0 to 15
p = .55
q = (1-.55)
c(n,x) = n! / (x! * (n-x)!


probabilities are shown in the excel printout below:


<img src = "http://theo.x10hosting.com/2024/012601.jpg">



the sum of all probabilities is p(x) from 0 to 15 and is equal to 1, as it should be.


answers to your questions are:


A. What is the probability of selecting 10 or more hospitals that have 100 or more beds?


p(10 or more) = sum p(x) for x = 10 to 15 = 0.260759769


B. What is the probability of selecting less than five hospitals that have 100 or more beds?


p(less than 5) = sum p(x) for x = 0 to 4 = 0.025465853


C. What is the probability of selecting from six to ten hospitals, inclusive, that have 100 or more beds?


p(6 to 10) = sum(p(x) for x = 6 to 10 = 0.802671982