If a seed is planted it has a 75% chance of growing into a healthy plant. If 8 seeds are planted what is the probability that exactly 4 don't grow?

Answer 1

If 4 don't grow, then that's the same as 4 growing.

p=0.75, q=0.25, n=8

P(X=4) = C(8,4)(0.75)⁴(0.25)⁴ ≈ 0.0865

Note that C(8,4) = 8!/[4!(8-4)!]

Hope this helped!