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Note that data headings are in Row 1, and data values are found in Rows 2-50. Column 1 contains the subject number, Column 2 contains the subjects composite ACT score, and Column 3 contains their freshman year GPA.
Assignment
1. Compute the descriptive statistics for the ACT scores. Print these values. Is this distribution skewed? If so, positively or negatively?
2. Compute the descriptive statistics for the GPA scores. Print these values. Is this distribution skewed? If so, positively or negatively?
3. Sort the data for all subjects by ACT scores.
4. Create a scatter graph (data points only, no lines) of GPA versus ACT scores. Print this graph.
5. Using class intervals (bins) of 5 and starting at 0 (0-5, 6-10, 11-15, etc.), plot a histogram of the ACT scores. Compute the relative frequency of each interval. Print the frequency table and the histogram. What percentage of students scored 20 or lower on the ACT?
6. Using 7 equally sized intervals, plot a histogram of the GPA scores. Compute the relative frequency of each interval. Print the frequency table and the histogram. What percentage of students had a GPA of 3.0 or higher?