Suppose that the following table gives the number of thousands of students in grades 9 through 12 for public schools in the U.S. Let X represent the grade level.
Grade(X)------9-------10------11-------12
Frequency--4048----3876---3108------3008
> Construct the probability distribution of X.
> Calculate the mean of X, and interpret the result.
> Calculate the variance of X.
> Calculate the standard deviation of X, and interpret the result.
> Estimate the dropout rate.