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Question
In a handloom factory different workers take different periods of time to weave a saree. The number of workers and their required periods are given below. Present the information by a frequency polygon.
|
No. of days
|
8 - 10 | 10 - 12 | 12 - 14 | 14 - 16 | 16 - 18 | 18 - 20 |
| No. of workers | 5 | 16 | 30 | 40 | 35 | 14 |
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Solution
Consider the following table
| Class (Number of days) |
Class Mark | Frequency (Number of workers) |
| 8 - 10 | 9 | 5 |
| 10 - 12 | 11 | 16 |
| 12 - 14 | 13 | 30 |
| 14 - 16 | 15 | 40 |
| 16 - 18 | 17 | 35 |
| 18 - 20 | 19 | 14 |
The frequency polygon using the class mark and frequancy given in the above table as
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When plotting a frequency polygon, which variable is taken on the y-axis?
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