Question

According to one study, 61% of the population swallow at least one spider per year in their sleep. Based on this study, what is the probability that exactly 7 of 10 randomly selected people have swallowed at least one spider in their sleep in the last year?

Answer 1

use binomial distribution
\[P(X=k) = \left(\begin{matrix}n \\ k\end{matrix}\right)p^{k}(1-p)^{n-k}\]
n=10
k = 7
p = 0.61