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3. A frequency distribution can be shown using a frequency polygon. 5 Frequency Polygons 5-9 0 10 15 20 10-14 15-19 20-24 25-30 Frequency Marks Test Scores A Frequency Polygon can be drawn onto an existing histogram.1. Mark the mid - points of each bar at the top with a point.2. Draw in straight lines connecting points.3. Extend lines if necessary ½ a class interval beyond first and last bars

4. Frequency Polygons 10 0 5 15 20 3040 50 Frequency Time in minutes Time Taken for Race 60

5. Frequency Polygons 10 0 5 15 20 15 2025 30 Frequency Temperature o C 35 Maximum Daily Temperature as Recorded by a Gardener

6. Worksheet 1 Frequency Polygons

7. A frequency polygon can be drawn directly from the frequency table by finding the mid-point of each class interval. 5 5-9 0 10 15 20 10-14 15-19 20-24 25-30 Frequency Marks Test Scores Marks5 – 910 – 1415 – 1920 – 2425 - 30 frequency41020138 712 17 2227.5

8. 10 0 5 15 20 3040 50 Frequency Time in minutes Time Taken for Race 60 A frequency polygon can be drawn directly from the frequency table by using by finding the mid-point of each class interval. Time10 – 2020 – 3030 – 4040 – 5050 - 60 frequency7101864

9. 10 0 5 15 20 15 2025 30 Frequency Temperature o C 35 Maximum Daily Temperature as Recorded by a Gardener Time10 – 1515 – 2020 – 2525 – 3030 - 35 frequency7151961 A frequency polygon can be drawn directly from the frequency table by using by finding the mid-point of each class interval.

10. Worksheet 2

11. 5 5-9 0 10 15 20 10-14 15-19 20-24 25-30 Frequency Marks Test Scores It is often useful to show frequency polygons, side by side, in order to compare distributions. The same 55 students sat two separate maths tests. The scores for each are shown by the frequency polygons below. Comment on the differences. Test 1 Test 2

12. 10 0 5 15 20 15 2025 30 Frequency Temperature o C 35 Maximum Daily Temperature as Recorded by a Gardener A gardener recorded the maximum daily temperature on 48 days throughout the year 2000. She repeated this for the same dates in 2003. Comment on the differences in temperature for these years. 2000 2003