Question

Suppose that the probability a seed will germinate is 80%. What is the probability that 7 of these seeds will germinate when 10 are planted? a. 1.0068 b. 25.17 c. 120 d. 0.201

Answer 1

Your answer will be letter B

Answer 2

Answer: d. 0.201

Explanation:

Given: The probability a seed will germinate = 80%

i.e.
`p= 0.8`

Then probability of a seed will not germinate is given by :-

`q= 1-p`

i.e
`q=1-0.8`

i.e.
`q=0.2`

By Binomial Distribution, the probability of getting r successes in n trials is given by :-

`P(r)=^nC_r\ p^rq^(n-r)`

Now , the probability that 7 (r=7) of these seeds will germinate when 10 (n=10) are planted is given by :-

`P(7)=^(10)C_7\ (0.8)^7(0.2)^(10-7)\\\\=(10!)/((10-7)!7!)(0.8)^7(0.2)^3\\\\=(10*9*8)/(3*2)(0.8)^7(0.2)^3\\\\=0.201326592\approx0.201`