Question

a random sample of 1000 people found that 250 people believe ghosts exists. assuming that the sample is representative of the population, construct a 95% confidence interval on the population proportion who belive in ghosts. what is the margin of error for this problem?

Answer 1

Solution :

Given that,

Point estimate = sample proportion = = x / n = 250 / 1000 = 0.250

1 - = 1 - 0.250 = 0.75

Z/2 = 1.96

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

= 1.96 * (((0.250 * 0.75) / 1000)

Margin of error = E = 0.027