How would you do this binomial distribution problem. I really dont get it.?

In a recent survey, 80% of the community favored building a police substation in their neighborhood. If 15 citizens are chosen, find the probability that exactly 10 of them favor the building of the police substation.

How would you do this binomial distribution problem. I really dont get it.?
For this problem, use the Binomial Probability Formula:





P(N) = N! / [k! * (N - k)!] * p^k * q^(N - k)





where:


N = Number of opportunities for event x to occur (15)


k = Number of times that event x should happen (10)


p = Probability of a success (.8)


q = Probability of failure (.2)


! = Factorial





P(k) = N! / [k! * (N - k)!] * p^k * q^(N - k)


P(10) = 15! / [10! * (15 - 10)!] * (.8)^10 * (.2)^(15 - 10)


P(10) = .1031822943191 or 10.32%





Yeah, the math gets really messy,


but you can use an online Binomial Probability Calculator:


http://faculty.vassar.edu/lowry/ch5apx.h...





Or you can do it on your TI-83/84 Calculator:


http://mathbits.com/MathBits/TISection/S...





Good luck in your studies,


~ Mitch ~