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For the grouped data below, what is the standard deviation of the distribution?
Class intervals: 0–10, 10–20, 20–30, 30–40
Frequencies: 1, 3, 4, 2
- 81
- 7.6
- 9
- 2.26
Correct answer: 9
Solution
The standard deviation is calculated based on the mean and the spread of the data points around that mean. In this case, the correct option reflects the calculated dispersion of the grouped data, indicating how much the values deviate from the average.
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