If a seed is planted, it has a 60% chance of growing into a healthy plant. If 12 seeds are planted, what is the probability that exactly 2 don't grow?

Answer 1

n = 12 seeds

p = 0.6 (seeds that will grow)

k = 10 seeds grow (2 seeds won't grow)

n choose k = 12 choose 10 = (12!)/(10!)[(12 - 10)!]

[12!/(10!)(2!)]*(0.6)¹⁰*(0.4)² ≈ 0.06385

This is the probability of exactly 2 seeds will not grow, which is the same as the probability of 10 seeds will grow.