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Math Question 11 Assignment from math book If a seed is planted, it has a 80% chance of growing into a healthy plant.If 10 seeds are planted, what is the probability that exactly 3 don't grow? Round your answer to three decimal places.A good calculator is found at: Stattrek Binomial Calculator ________.

Math Question 11 Assignment from math book If a seed is planted, it has a 80% chance-example-1
User Jun Kang
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1 Answer

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Given:

If a seed is planted, it has a 80% chance of growing into a healthy plant.

10 seeds are planted.

Required:

To find the probability that exactly 3 don't grow.

Step-by-step explanation:


\begin{gathered} p=80\% \\ \\ =0.8 \\ \\ 1-p=1-0.8 \\ \\ =0.2 \end{gathered}
\begin{gathered} N=10 \\ k=3 \end{gathered}

Seven success in 10 trails, therefore


\begin{gathered} =(10\text{ choose 7\rparen}*(0.8)^7*(0.2)^3 \\ \\ =((10*9*8))/((3*2))*(0.8)^7*(0.2)^3 \\ \\ =(5*3*8)*0.2097*0.008 \end{gathered}
=0.2013

Therefore 20% that exactly 3 don't grow.

Final Answer:


20\%

User Jordan Brough
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