Answer:
The confidence Interval = (0.329, 0.391)
Step-by-step explanation:
Formula for the Confidence Interval for proportion =
p ± z × √p(1 - p)/n
where
p = x/n
From the question
n = 900 people
x = 36% of 900 people
= 36/100 × 900
= 324
z = z score of 95% confidence Interval
z = 1.98
p = x/n
= 324/900
= 0.36
Confidence Interval = p ± z × √p(1 - p)/n
= 0.36 ± 1.96 × √0.36 (1 - 0.36)/900
= 0.36 ± 1.96 ×√0.36 (0.64)/900
= 0.36 ± 1.96 × √0.000256
= 0.36 ± 1.96 × 0.016
= 0.36 ± 0.03136
Confidence Interval = 0.36 ± 0.03136
= 0.36 - 0.03136
= 0.32864
Approximately to 3 decimal places = 0.329
= 0.36 + 0.03136
= 0.39136
Approximately to 3 decimal places = 0.391
Therefore, the 95% confidence interval for the population proportion of people who believe the governor broke campaign financing laws = (0.329, 0.391)
