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प्रश्न
The following cumulative frequency distribution table shows the daily electricity consumption (in kW) of 40 factories in an industrial state:
| Consumption (in kW) | No. of Factories |
| Below 240 | 1 |
| Below 270 | 4 |
| Below 300 | 8 |
| Below 330 | 24 |
| Below 360 | 33 |
| Below 390 | 38 |
| Below 420 | 40 |
(i) Represent this as a frequency distribution table.
(ii) Prepare a cumulative frequency table.
उत्तर
(i)
| Consumption (in kW) | No. of factories | Class interval | Frequency |
| Below 240 | 1 | 0-240 | 1 |
| Below 270 | 4 | 240-270 | 4-1=3 |
| Below 300 | 8 | 270-300 | 8-4=4 |
| Below 330 | 24 | 300-330 | 24-8=16 |
| Below 360 | 33 | 330-360 | 33-24=9 |
| Below 390 | 38 | 360-390 | 38-33=5 |
| Below 420 | 40 | 390-420 | 40-38=2 |
(ii)
| Class interval | Frequency | Consumption (in kw) | No. of factories |
| 0-240 | 1 | More than 0 | 40 |
| 240-270 | 3 | More than 240 | 40-1=39 |
| 270-300 | 4 | More than 270 | 39-3=36 |
| 300-330 | 16 | More than 300 | 36-4=32 |
| 330-360 | 9 | More than 330 | 32-16=16 |
| 360-390 | 5 | More than 360 | 16-9=7 |
| 390-420 | 2 | More than 390 | 7-5=2 |
| More than 420 | 2-2=0 | ||
| N = 40 |
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| 161 | 150 | 154 | 165 | 168 | 161 | 154 | 162 | 150 | 151 |
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| 170 – 173 | 6 |
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