Example of Empirical Rule
• A certain standardized test's math scores have a bell-shaped
distribution with a mean of 520 and a standard deviation of 119 .
Complete parts (a) through (c).
• (a) What percentage of standardized test scores is between 401 and
639? (Round to one decimal place as needed.)
• (b) What percentage of standardized test scores is less than 401 or
greater than 639? (Round to one decimal place as needed.)
• (c) What percentage of standardized test scores is greater than 758?
(Round to one decimal place as needed.)