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प्रश्न
The following table gives the weekly wages of workers in a factory.
| Weekly wages (Rs) | No. of workers |
| 50 – 55 | 5 |
| 55 – 60 | 20 |
| 60 – 65 | 10 |
| 65 – 70 | 10 |
| 70 – 75 | 9 |
| 75 – 80 | 6 |
| 80 – 85 | 12 |
| 85 – 90 | 8 |
Calculate the mean by using:
Short-cut method
उत्तर
Short-cut method
|
Weekly wages |
No. of workers |
Mid-value |
A = 72.5 |
fidi |
| 50 – 55 | 5 | 52.5 | –20 | –100 |
| 55 – 60 | 20 | 57.5 | –15 | –300 |
| 60 – 65 | 10 | 62.5 | –10 | –100 |
| 65 – 70 | 10 | 67.5 | –5 | –50 |
| 70 – 75 | 9 | A = 72.5 | 0 | 0 |
| 75 – 80 | 6 | 77.5 | 5 | 30 |
| 80 – 85 | 12 | 82.5 | 10 | 120 |
| 85 – 90 | 8 | 87.5 | 15 | 120 |
| Total | 80 | –280 |
`barx = A + (sumf_i d_i)/(sumf_i)`
= `72.5 + ((-280)/80)`
= 72.5 – 3.5
= 69
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