Question

A research company recently surveyed 8217 adults in one country about reform of the​ country's senate. Of​ these, 33% answered​ "Yes" to the question​ "Do you support abolishing the​ senate?". What is the margin of error for a 90% confidence interval for the population proportion based on this sample?

Answer 1

Solution :

Given that,

Point estimate = sample proportion = = 0.33

1 - = 1 - 0.33 = 0.67

Z/2 = 1.645

Margin of error = E = Z / 2 * (( * (1 - )) / n)

= 1.645 * (((0.33 * 0.67) / 8217)

Margin of error = E = 0.009