SOLUTION: Suppose that IQ scores have a bell-shaped distribution with a mean of 104 and a standard deviation of 17. Using the empirical rule, what percentage of IQ scores are between 87 and

Hi  

Normal Distribution:   μ = 104 and  σ = 17  
percentage of IQ scores are between 87 and 121? 
Each 17 from mean:  between z = -1  and z = 1

one  standard deviation from the mean accounts for about 68.2% of the set***** 
two standard deviations from the mean account for about 95.4%
and three standard deviations from the mean account for about 99.7%.
Important to Understand z -values as they relate to the Standard Normal curve:


Wish You the Best in your Studies.