Answer:
The Confidence Interval(CI) is calculated as (0.043, 0.257).
The steps and expanation is shown below.
Explanation:
The formula for a Confidence Interval(CI) for a population proportion is given as
p + z*[Sqrt(p(1 - p))/n]
Or
p - z*[Sqrt(p(1 - p))/n],
p is the sample proportion, n is the sample size, and z* is the appropriate value from the standard normal distribution for your desired confidence level. The following table shows values of z* for certain confidence levels.
For the 98% Confidence Interval, z*–value = 2.33
p = 9/60 = 0.15, confidence level z* = 2.33( From the standard table)
0.15 + 2.33[Sqrt(0.15(1 - 0.15))/60]
OR
0.15 - 2.33[Sqrt(0.15(1 - 0.15))/60]
0.15 + 0.107 or 0.15 - 0.107
Confidence Interval is
(0.043, 0.257)