Question 1: Given the cumulative frequency data: 0, 5, 12, 20, 29, 35, 38. Plot the cumulative frequency graph corresponding to these values against the class boundaries 10, 20, 30, 40, 50, 60, 70.

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Question 2: Using the plotted graph, estimate the median class boundary.

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Question 3: Construct a cumulative frequency graph for the following data: Number of students in each score range: 0-10: 3, 10-20: 7, 20-30: 12, 30-40: 20, 40-50: 25. Plot the graph with appropriate axes.

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Question 4: A teacher records the number of books read by students in a month. The cumulative frequency at 5, 10, 15, 20 books are 8, 18, 25, 30 respectively. Plot the cumulative frequency curve.

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Question 5: Identify and correct the mistake in the following cumulative frequency plot: the graph jumps backwards at some point.

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Question 6: Given a cumulative frequency table, plot the graph and then determine the number of students who scored above 70.

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Question 7: Explain why the cumulative frequency graph levels off at the highest value.

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Question 8: Plot the cumulative frequency for data: 10, 15, 20, 25, 30. The total number of observations is 50, with data points at 10, 15, 20, 25, 30, and the cumulative totals are 5, 15, 25, 35, 50 respectively. Draw and label the graph.

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Question 9: A cumulative frequency graph appears to be incorrectly scaled. Describe how to identify and fix the scale issue.

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Question 10: Using the plotted graph, find the interquartile range for the data set.

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Question 11: Challenge: Given a cumulative frequency table with irregular intervals, plot the graph and then interpolate to estimate the number of students who scored between 65 and 75.

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Question 12: Identify common errors students make when plotting cumulative frequency graphs and suggest strategies to avoid them.

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