A random sample of 10000 people was chosen for a survey 2 of

A random sample of 10,000 people was chosen for a survey, 2% of them owned horses.

Find the 95% confidence interval

Use standard deviation, Round your answers to 3 significant digits. Give the lowest and higest values of the confidence interval separated by a dash. (Remember: Leading zeroes are NOT signifciant!)

Solution

A random sample of 10000 people was chosen for a survey and 2% of them owned horses.

Here, n = 10000 and p = 0.02

The standard deviation is [sqrt(10000*0.02*0.98)] = 14

The mean is 10000*0.02 = 200

The 95% confidence interval is 200 + 1.96*14 = 227.44 and 200 - 1.96*14 = 172.56

The lower and higher limits of the 95% confidence interval are 172.56 and 227.44