Answer:
The critical value of <em>z</em> for 99% confidence interval is 2.5760.
The 99% confidence interval for population mean number of lightning strike is (7.83 mn, 8.37 mn).
Step-by-step explanation:
Let <em>X</em> = number of lightning strikes on each day.
A random sample of <em>n</em> = 23 days is selected to observe the number of lightning strikes on each day.
The random variable <em>X</em> has a sample mean of, and the population standard deviation,
.
The (1 - <em>α</em>)% confidence interval for population mean <em>μ</em> is:
Compute the critical value of <em>z</em> for 99% confidence interval is:
*Use a <em>z</em>-table.
The critical value of <em>z</em> for 99% confidence interval is 2.5760.
Compute the 99% confidence interval for population mean number of lightning strike as follows:
Thus, the 99% confidence interval for population mean number of lightning strike is (7.83 mn, 8.37 mn).
The 99% confidence interval for population mean number of lightning strike implies that the true mean number of lightning strikes lies in the interval (7.83 mn, 8.37 mn) with 0.99 probability.