Question

In a random sample of 100 people, 49 consider themselves as basketball fans. Compute a 90% confidence interval for the true proportion of people consider themselves as basketball fans and fill in the blanks appropriately.

We are __% confidence that the true proportion of people consider themselves as basketball fans is between ___ and ___ . (Keep 3 decimal places)

Answer 1

Sample size, n = 100

Sample proportion, = 49/100 = 0.49

Confidence interval, CI = Z*

For 90% confidence level, Z* = 1.645

CI = 0.49 1.645 x

= 0.49 0.05

= (0.44, 0.54)

We are 90% confidence that the true proportion of people consider themselves as basketball fans is between 0.44 and 0.54.