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Question
Construct a frequency polygon for the following distribution:
| Class-intervals | 0-4 | 4 - 8 | 8 - 12 | 12 - 16 | 16 - 20 | 20 - 24 |
| Frequency | 4 | 7 | 10 | 15 | 11 | 6 |
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Solution
The frequency polygon is shown in the following figure
Steps:
(i) Drawing a histogram for the given data.
(ii) Marking the mid-point at the top of each rectangle of the histogram drawn.
(iii) Also, marking mid-point of the immediately lower class-interval and mid-point of the immediately higher class-interval.
(iv) Joining the consecutive mid-points marked by straight lines to obtain the required frequency polygon.
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