Question

According to an online poll, 40100 people out of 44700 people surveyed think that the Charleston Chiefs will win their game against the Halifax Highlanders. Find a 90% confidence interval for p, the percentage of people who thinks that the Charleston Chiefs will win the game. Also find the margin of error. Round your answers to 3 decimal places.

Answer 1

Solution :

Given that,

Point estimate () = x / n = 40100 / 44700 = 0.897

1 - = 0.103‬

Z/2 = 1.645

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

= 1.645 * (((0.897 * 0.103) / 44700)

= 0.002

A 90% confidence interval for population proportion p is ,

- E < p < + E

0.897 - 0.002 < p < 0.897 + 0.002

0.895 < p < 0.899

(0.895, 0.899)