The daily commute time for employees at a tech firm is normally distributed with a mean of 45 minutes and a standard deviation of 6 minutes.
Find the probability of a commute taking longer than 58 minutes.
Write down a null and alternative hypothesis for a two-tailed test.
A survey of 12 randomly selected employees finds a mean commute time of 49.5 minutes. Test at the 10% significance level whether there is evidence that the mean commute time has changed.