If a seed is planted, it has a 65% chance of growing into a healthy plant. If 7 seeds are planted, what is the probability that exactly 1 doesn't grow?

Answer 1

7 seeds planted, 65% each will grow healthy

probability that exactly 1 will not grow healthy?

odds none grow healthy = P(0) = 7C7(.65)^0(.35)^7=.35^7

odds 6 grow healthy = P(6) = 7C6(.65)^6(.35)^1 = P(1) doesn't grow healthy)

= 7!/6!(.65)^6(.35)

=7(.35)(.65)^6

=2.45(.65)^6

=2.45(.0754)

=about .185

= about 18.5% chance exactly one is not healthy