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प्रश्न
A milk centre sold milk to 50 customers. The table below gives the number of customers and the milk they purchased. Find the mean of the milk sold by direct method.
| Milk Sold (Litre) | 1 – 2 | 2 – 3 | 3 – 4 | 4 – 5 | 5 – 6 |
| No. of Customers | 17 | 13 | 10 | 7 | 3 |
उत्तर
|
Class
(Milk sold in litres) |
Class Mark xi |
Frequency (Number of customers) fi |
Class mark × Frequency fixi |
| 1 – 2 | 1.5 | 17 | 25.5 |
| 2 – 3 | 2.5 | 13 | 32.5 |
| 3 – 4 | 3.5 | 10 | 35 |
| 4 – 5 | 4.5 | 7 | 31.5 |
| 5 – 6 | 5.5 | 3 | 16.5 |
| Total | – | `sumf_i` = 50 | `sumf_i x_i` = 141 |
Mean = `(sumf_i x_i)/(sumf_i)`
= `141/50`
= 2.82 litres
Hence, the mean of the milk sold is 2.82 litres.
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