Researchers S. Lesik and M. Mitchell explore the difficulty of predicting success in college-level mathematics in the article "The Investigation of Multiple Paths to Success in College-Level Mathematics" (Journal of Applied Research in Higher Education, Vol. 5, Issue 1, pp. 48-57). One of the variables explored as an indicator of success was the length of time since a college freshman has taken a mathematics course. The article reports that the mean length of time is 0.18 years with a standard deviation of 0.624 years. For college freshmen, let x represent the time, in years, since taking
a math course.
a. What percentage of times are at least 0 years?
b. Assuming that x is approximately normally distributed, use normal curve areas to determine the approximate percentage of times that are at least 0 years.
c. Based on your results from parts (a) and (b), do you think that the length of time since taking a math course for college freshmen is approximately a normally distributed variable? Explain your answer.