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प्रश्न
If the variance of a data is 121, then the standard deviation of the data is ______.
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उत्तर
If the variance of a data is 121, then the standard deviation of the data is 11.
Explanation:
We know that S.D. = `sqrt("Variance")`
= `sqrt(121)`
= 11
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संबंधित प्रश्न
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| xi | 92 | 93 | 97 | 98 | 102 | 104 | 109 |
| fi | 3 | 2 | 3 | 2 | 6 | 3 | 3 |
The diameters of circles (in mm) drawn in a design are given below:
| Diameters | 33 - 36 | 37 - 40 | 41 - 44 | 45 - 48 | 49 - 52 |
| No. of circles | 15 | 17 | 21 | 22 | 25 |
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|
No. of goals scored |
0 |
1 |
2 |
3 |
4 |
|
No. of matches |
1 |
9 |
7 |
5 |
3 |
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|
Subject |
Mathematics |
Physics |
Chemistry |
|
Mean |
42 |
32 |
40.9 |
|
Standard deviation |
12 |
15 |
20 |
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| fi: | 6 | 4 | 5 | 1 |
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Factory B (Number of bulbs) |
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| 120 | 120 |
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