Complete question:
On the package for a certain brand of spinach seeds there is a guarantee that, if the printed instructions are followed, 63% of planted seeds will germinate. A random sample of 9 seeds is chosen. If these seeds are planted according to the instructions, find the probability that 4 of them germinate.
Answer:
[tex]P(x = 4) = 0.1376[/tex]
Step-by-step explanation:
Given
[tex]n = 9[/tex]
[tex]p = 63\%[/tex] --- proportion that germinates
[tex]p = 0.63[/tex]
Required
P(x = 4)
This question follows a binomial distribution:
[tex]P(x) = ^nC_x*p^x*(1-p)^{n-x[/tex]
When x = 4;
[tex]P(x = 4) = ^9C_4*0.63^4*(1-0.63)^{9-4[/tex]
[tex]P(x = 4) = ^9C_4*0.63^4*(0.37)^5[/tex]
[tex]P(x = 4) = 126*0.63^4*0.37^5[/tex]
[tex]P(x = 4) = 0.13763895392[/tex]
[tex]P(x = 4) = 0.1376[/tex]