Answer:
Step-by-step explanation:
Using normal distribution
z = (x - mean) / standard deviation
Nine percent of americans say they are well informed about politics in comparison to most people.
That means probability of success is p =9/100 = 0.09,
then probability of failure is
q = 1-p =1 -0.09= 0.91
n = number of sample = 200
x=(8% of 200) = 0.08×200 =16
mean = np = 200×0.09= 18
Standard deviation = npq = 200×0.09×0.91= 16.38
We are looking for the probability that less than 8% of the people sampled will answer yes to the question
8% of 200 = 16
P (x greater than 16) =P(x lesser than/equal to 15)
z = 15-18 /16.38 = -3/16.38
= -0.18
Looking at the normal distribution table
P(x greater than 16) = 0.5714
