Question

An allergist claims that 50% of the patients she tested are allergic to some type of weed. What is the probability that exactly 3 of her next 4 patients are allergic to weeds?

What is he probability that none of her next 4 patients are allergic to weeds?

Answer 1

`.25`

Explanation:

Since the allergist wants to know the probability of exactly `3` and that there's a set number of trials with a given probability, we use `bpdf`. The probability is `.50`, the number of trials is `4`, and the x value is `3`:

`bpdf(4,.5,3)=.25`