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If the variance of the frequency distribution is 160, then the value of c ∈ N is x: c, 2c, 3c, 4c, 5c, 6c f: 2, 1, 1, 1, 1, 1
- 5
- 8
- 7
- 6
Correct answer: 7
Solution
The variance is calculated using the formula that incorporates the mean and the squared deviations of each value from the mean, weighted by their frequencies. In this case, the correct value of c is determined to ensure that the calculated variance equals 160, which is satisfied when c equals 7.
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