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Question
The daily wages in a factory are distributed as follows:
|
Daily wages (in Rs.) |
125 - 175 |
175 - 225 |
225 - 275 |
275 - 325 |
325 - 375 |
|
Number of workers |
4 |
20 |
22 |
10 |
6 |
Draw a frequency polygon for this distribution.
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Solution
Steps:
- Draw a histogram for the given data.
- Mark the mid-point at the top of each rectangle of the histogram drawn.
- Also, mark the mid-point of the immediately lower class-interval and mid-point of the immediately higher class-interval.
- Join the consecutive mid-points marked by straight lines to obtain the required frequency polygon.
The required frequency polygon is as follows:
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