In a sample of 7 trees, what is the probability that exactly 2 of the trees are adults, assuming that the prevalence of adult trees is 60%.
Prob(mature tree) = 6/10 = 3/5
Prob(immature tree) = 2/5
prob(exactly 2 of 7 trees mature)
= C(7,2) (3/5)^2 (2/5)^5
= 21(9/25)(32/3125) = 6048/78125
= appr .0774