According to the empirical XXXXXXXXXXrule, if a random variable ?z has a standard normal distribution, then approximately 95% of all values fall between ?z‑scores of –2 and 2. Use the standard normal...

According to the empirical (68-95-99.7) rule, if a random variable ?z has a standard normal distribution, then approximately 95% of all values fall between ?z‑scores of –2 and 2. Use the standard normal table or software to determine the precise positive value of ?z such that 95% of the area under the standard normal density curve is between −z and z. If you use software, you may find this list of manuals useful