Question

The grades on the last math exam had a mean of 88%. Assume the population of grades on math exams is known to be normally distributed with a standard deviation of 6. What percent of students earn a score between 72% and 90%? (

Answer 1

What methods have you used to solve similar problems in the past? Among the possibilities are:

1) z-scores, used to find areas under the standard normal curve to the left of any given z score
2) TI-83 or TI-84 Calculator: Use the DISTR key to find normalcdf( ... )