In the business world, the mean salary is often used to describe the salaries of employees of a company. However, the median salary may be a better measure of the salaries than the mean. Which is the better measure of central tendency? and Why? 



The number of vacation days taken by employees of a company is normally distributed with a mean of 14 days and a standard deviation of 3 days. For the next employee, what is the probability that the number of days of vacation taken is less than 10 days? More than 21 days?