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प्रश्न
The following frequency distribution table shows the amount of aid given to 50 flood affected families. Find the mean of the amount of aid.
|
Amount of aid
(Thousand rupees)
|
50 - 60 | 60 - 70 | 70 - 80 | 80 - 90 | 90 - 100 |
| No. of families | 7 | 13 | 20 | 6 | 4 |
उत्तर
|
Class
(Amount of aid in thousand rupees) |
Class Mark xi |
Frequency (Number of families) fi |
Class mark × Frequency xifi |
| 50 - 60 | 55 | 7 | 385 |
| 60 - 70 | 65 | 13 | 845 |
| 70 - 80 | 75 | 20 | 1500 |
| 80 - 90 | 85 | 6 | 510 |
| 90 - 100 | 95 | 4 | 380 |
| `sum f_i ` = 50 | `sum x_i f_i = 3620` |
Mean = `(sum x_i f_i )/(sum f_i)`
`= 3620/50`
= 72.4 thousand rupees
= Rs 72400
Hence, the mean of the amount of aid is Rs 72400.
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संबंधित प्रश्न
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|
Daily wages (in Rs) |
100 − 120 |
120 − 140 |
140 −1 60 |
160 − 180 |
180 − 200 |
|
Number of workers |
12 |
14 |
8 |
6 |
10 |
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If the mean of the following data is 20.6. Find the value of p.
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| f | 3 | 10 | 25 | 7 | 5 |
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| Age (in years) | 15 | 16 | 17 | 18 | 19 | 20 |
| No. of students | 3 | 8 | 10 | 10 | 5 | 4 |
The arithmetic mean of the following data is 25, find the value of k.
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| x | 10 | 15 | P | 25 | 30 |
| f | 5 | 10 | 7 | 8 | 2 |
Find the mean of each of the following frequency distributions
| Class interval | 0 - 8 | 8 - 16 | 16 - 24 | 24 - 32 | 32 - 40 |
| Frequency | 6 | 7 | 10 | 8 | 9 |
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| Size of item | 1 - 4 | 4 - 9 | 9 - 16 | 16 - 27 |
| Frequency | 6 | 12 | 26 | 20 |
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| Marks: | 0 - 10 | 10 - 20 | 20 - 30 | 30 - 40 | 40 - 50 |
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| No. of cases | 6 | 11 | 21 | 23 | 14 | 5 |
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|
Weekly wages
(Rupees)
|
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| Number of days: | 0-6 | 6-12 | 12-18 | 18-24 | 24-30 | 30-36 | 36-42 |
| Number of students: | 10 | 11 | 7 | 4 | 4 | 3 | 1 |
Find the mean of the following distribution:
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| Frequency | 10 | 6 | 8 | 12 | 5 |
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| 0.00 - 0.04 | 4 | 0.02 | -0.08 |
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