Answer:
Mean of the binomial distribution μ= 6
Variance of the binomial distribution λ² = 4.2
Step-by-step explanation:
Explanation:-
The probability a Gallup poll showed that 30% of Americans are satisfied with the way things are going in the United States.
p = 30% = 0.3
q =1-p = 1- 0.3 =0.7
a sample of 20 Americans is selected as part of a study of the state of the nation
size of the sample 'n' =20
we will use binomial distribution
mean:-
Mean of Americans who are satisfied with the way things are going in the United States (μ) = np
μ= 20 X 0.3
μ= 6
Variance:-
Variance of Americans who are satisfied with the way things are going in the United States λ² = n p q = 20 X(0.3)(0.7)
λ² = 4.2
