Question

22 random samples were selected from a population that has a normal distribution the sample has a mean of 99 and a standard deviation of 5 construct a 95% confidence interval for the population standard deviation .

Answer 1

4, 7

Explanation:

gradpoint

Answer 2

(96.91, 101.09)

Explanation:

To calculate the interval, you require the Z value at 95% confidence interval. The Z value is 1.96. The formula to calculate the confidence interval:

`X-Zs/√(x) \\X+Zs/√(x)`

Where X is the mean and s is the standard deviation and x the sample size:

`99-1.96\cdot{5}/√(22) \\99+1.96\cdot{5}/√(22)`

The interval is (96.91, 101.09)